use optimization level 3 and thin LTO for release builds (#1405)

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/1405
Co-authored-by: Alex Auvolat <lx@deuxfleurs.fr>
Co-committed-by: Alex Auvolat <lx@deuxfleurs.fr>

.cargo/config.toml

@@ -1,3 +0,0 @@
-[target.x86_64-unknown-linux-gnu]
-linker = "clang"
-rustflags = ["-C", "link-arg=-fuse-ld=mold"]

.drone.yml

@@ -1,300 +0,0 @@
----
-kind: pipeline
-name: default
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: check formatting
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-shell --attr rust --run "cargo fmt -- --check"
-
-  - name: build
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr clippy.amd64 --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-
-  - name: unit + func tests
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      GARAGE_TEST_INTEGRATION_EXE: result-bin/bin/garage
-      GARAGE_TEST_INTEGRATION_PATH: tmp-garage-integration
-    commands:
-      - nix-build --no-build-output --attr clippy.amd64 --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-build --no-build-output --attr test.amd64
-      - ./result/bin/garage_db-*
-      - ./result/bin/garage_api-*
-      - ./result/bin/garage_model-*
-      - ./result/bin/garage_rpc-*
-      - ./result/bin/garage_table-*
-      - ./result/bin/garage_util-*
-      - ./result/bin/garage_web-*
-      - ./result/bin/garage-*
-      - ./result/bin/integration-* || (cat tmp-garage-integration/stderr.log; false)
-      - rm result
-      - rm -rv tmp-garage-integration
-
-  - name: integration tests
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr clippy.amd64 --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr integration --run ./script/test-smoke.sh || (cat /tmp/garage.log; false)
-
-trigger:
-  event:
-  - custom
-  - push
-  - pull_request
-  - tag
-  - cron
-
----
-kind: pipeline
-type: docker
-name: release-linux-amd64
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: build
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr pkgs.amd64.release --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr rust --run "./script/not-dynamic.sh result-bin/bin/garage"
-
-  - name: integration tests
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-shell --attr integration --run ./script/test-smoke.sh || (cat /tmp/garage.log; false)
-
-  - name: upgrade tests
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-shell --attr integration --run "./script/test-upgrade.sh v0.8.4 x86_64-unknown-linux-musl" || (cat /tmp/garage.log; false)
-
-  - name: push static binary
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      AWS_ACCESS_KEY_ID:
-        from_secret: garagehq_aws_access_key_id
-      AWS_SECRET_ACCESS_KEY:
-        from_secret: garagehq_aws_secret_access_key
-      TARGET: "x86_64-unknown-linux-musl"
-    commands:
-      - nix-shell --attr release --run "to_s3"
-
-  - name: docker build and publish
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      DOCKER_AUTH:
-        from_secret: docker_auth
-      DOCKER_PLATFORM: "linux/amd64"
-      CONTAINER_NAME: "dxflrs/amd64_garage"
-      HOME: "/kaniko"
-    commands:
-      - mkdir -p /kaniko/.docker
-      - echo $DOCKER_AUTH > /kaniko/.docker/config.json
-      - export CONTAINER_TAG=${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr release --run "to_docker"
-
-
-trigger:
-  event:
-  - promote
-  - cron
-
----
-kind: pipeline
-type: docker
-name: release-linux-i386
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: build
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr pkgs.i386.release --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr rust --run "./script/not-dynamic.sh result-bin/bin/garage"
-
-  - name: integration tests
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-shell --attr integration --run ./script/test-smoke.sh || (cat /tmp/garage.log; false)
-
-  - name: upgrade tests
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-shell --attr integration --run "./script/test-upgrade.sh v0.8.4 i686-unknown-linux-musl" || (cat /tmp/garage.log; false)
-
-  - name: push static binary
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      AWS_ACCESS_KEY_ID:
-        from_secret: garagehq_aws_access_key_id
-      AWS_SECRET_ACCESS_KEY:
-        from_secret: garagehq_aws_secret_access_key
-      TARGET: "i686-unknown-linux-musl"
-    commands:
-      - nix-shell --attr release --run "to_s3"
-
-  - name: docker build and publish
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      DOCKER_AUTH:
-        from_secret: docker_auth
-      DOCKER_PLATFORM: "linux/386"
-      CONTAINER_NAME: "dxflrs/386_garage"
-      HOME: "/kaniko"
-    commands:
-      - mkdir -p /kaniko/.docker
-      - echo $DOCKER_AUTH > /kaniko/.docker/config.json
-      - export CONTAINER_TAG=${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr release --run "to_docker"
-
-trigger:
-  event:
-  - promote
-  - cron
-
----
-kind: pipeline
-type: docker
-name: release-linux-arm64
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: build
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr pkgs.arm64.release --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr rust --run "./script/not-dynamic.sh result-bin/bin/garage"
-
-  - name: push static binary
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      AWS_ACCESS_KEY_ID:
-        from_secret: garagehq_aws_access_key_id
-      AWS_SECRET_ACCESS_KEY:
-        from_secret: garagehq_aws_secret_access_key
-      TARGET: "aarch64-unknown-linux-musl"
-    commands:
-      - nix-shell --attr release --run "to_s3"
-
-  - name: docker build and publish
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      DOCKER_AUTH:
-        from_secret: docker_auth
-      DOCKER_PLATFORM: "linux/arm64"
-      CONTAINER_NAME: "dxflrs/arm64_garage"
-      HOME: "/kaniko"
-    commands:
-      - mkdir -p /kaniko/.docker
-      - echo $DOCKER_AUTH > /kaniko/.docker/config.json
-      - export CONTAINER_TAG=${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr release --run "to_docker"
-
-trigger:
-  event:
-  - promote
-  - cron
-
----
-kind: pipeline
-type: docker
-name: release-linux-arm
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: build
-    image: nixpkgs/nix:nixos-22.05
-    commands:
-      - nix-build --no-build-output --attr pkgs.arm.release --argstr git_version ${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr rust --run "./script/not-dynamic.sh result-bin/bin/garage"
-
-  - name: push static binary
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      AWS_ACCESS_KEY_ID:
-        from_secret: garagehq_aws_access_key_id
-      AWS_SECRET_ACCESS_KEY:
-        from_secret: garagehq_aws_secret_access_key
-      TARGET: "armv6l-unknown-linux-musleabihf"
-    commands:
-      - nix-shell --attr release --run "to_s3"
-
-  - name: docker build and publish
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      DOCKER_AUTH:
-        from_secret: docker_auth
-      DOCKER_PLATFORM: "linux/arm"
-      CONTAINER_NAME: "dxflrs/arm_garage"
-      HOME: "/kaniko"
-    commands:
-      - mkdir -p /kaniko/.docker
-      - echo $DOCKER_AUTH > /kaniko/.docker/config.json
-      - export CONTAINER_TAG=${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr release --run "to_docker"
-
-trigger:
-  event:
-  - promote
-  - cron
-
----
-kind: pipeline
-type: docker
-name: refresh-release-page
-
-node:
-  nix-daemon: 1
-
-steps:
-  - name: multiarch-docker
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      DOCKER_AUTH:
-        from_secret: docker_auth
-      HOME: "/root"
-    commands:
-      - mkdir -p /root/.docker
-      - echo $DOCKER_AUTH > /root/.docker/config.json
-      - export CONTAINER_TAG=${DRONE_TAG:-$DRONE_COMMIT}
-      - nix-shell --attr release --run "multiarch_docker"
-  - name: refresh-index
-    image: nixpkgs/nix:nixos-22.05
-    environment:
-      AWS_ACCESS_KEY_ID:
-        from_secret: garagehq_aws_access_key_id
-      AWS_SECRET_ACCESS_KEY:
-        from_secret: garagehq_aws_secret_access_key
-    commands:
-      - mkdir -p /etc/nix && cp nix/nix.conf /etc/nix/nix.conf
-      - nix-shell --attr release --run "refresh_index"
-
-depends_on:
-  - release-linux-amd64
-  - release-linux-i386
-  - release-linux-arm64
-  - release-linux-arm
-
-trigger:
-  event:
-  - promote
-  - cron
-
----
-kind: signature
-hmac: 0c4b57eb4b27b7c6a6ff21ab87f0767fe3eb90f5d95d5cbcdccf794e9d2a5d86
-
-...

.woodpecker/debug.yaml

@@ -0,0 +1,44 @@
+labels:
+  nix: "enabled"
+
+when:
+  event:
+  - push
+  - tag
+  - pull_request
+  - deployment
+  - cron
+  - manual
+
+steps:
+  - name: check formatting
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.fmt
+
+  - name: build
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.dev
+
+  - name: unit + func tests (lmdb)
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.tests-lmdb
+
+  - name: unit + func tests (sqlite)
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.tests-sqlite
+
+  - name: unit + func tests (fjall)
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.tests-fjall
+
+  - name: integration tests
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build -j4 --attr flakePackages.dev
+      - nix-shell --attr ci --run ./script/test-smoke.sh || (cat /tmp/garage.log; false)
+    depends_on: [ build ]

.woodpecker/publish.yaml

@@ -0,0 +1,33 @@
+labels:
+  nix: "enabled"
+
+when:
+  event:
+  - deployment
+  - cron
+
+depends_on:
+  - release
+
+steps:
+  - name: refresh-index
+    image: nixpkgs/nix:nixos-24.05
+    environment:
+      AWS_ACCESS_KEY_ID:
+        from_secret: garagehq_aws_access_key_id
+      AWS_SECRET_ACCESS_KEY:
+        from_secret: garagehq_aws_secret_access_key
+    commands:
+      - mkdir -p /etc/nix && cp nix/nix.conf /etc/nix/nix.conf
+      - nix-shell --attr ci --run "refresh_index"
+
+  - name: multiarch-docker
+    image: nixpkgs/nix:nixos-24.05
+    environment:
+      DOCKER_AUTH:
+        from_secret: docker_auth
+    commands:
+      - mkdir -p /root/.docker
+      - echo $DOCKER_AUTH > /root/.docker/config.json
+      - export CONTAINER_TAG=${CI_COMMIT_TAG:-$CI_COMMIT_SHA}
+      - nix-shell --attr ci --run "multiarch_docker"

.woodpecker/release.yaml

@@ -0,0 +1,71 @@
+labels:
+  nix: "enabled"
+
+when:
+  event:
+  - deployment
+  - cron
+
+matrix:
+  include:
+    - ARCH: amd64
+      TARGET: x86_64-unknown-linux-musl
+    - ARCH: i386
+      TARGET: i686-unknown-linux-musl
+    - ARCH: arm64
+      TARGET: aarch64-unknown-linux-musl
+    - ARCH: arm
+      TARGET: armv6l-unknown-linux-musleabihf
+
+steps:
+  - name: build
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-build --attr releasePackages.${ARCH} --argstr git_version ${CI_COMMIT_TAG:-$CI_COMMIT_SHA}
+
+  - name: check is static binary
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-shell --attr ci --run "./script/not-dynamic.sh result/bin/garage"
+
+  - name: integration tests
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-shell --attr ci --run ./script/test-smoke.sh || (cat /tmp/garage.log; false)
+    when:
+      - matrix:
+          ARCH: amd64
+      - matrix:
+          ARCH: i386
+
+  - name: upgrade tests
+    image: nixpkgs/nix:nixos-24.05
+    commands:
+      - nix-shell --attr ci --run "./script/test-upgrade.sh v0.8.4 x86_64-unknown-linux-musl" || (cat /tmp/garage.log; false)
+    when:
+      - matrix:
+          ARCH: amd64
+
+  - name: push static binary
+    image: nixpkgs/nix:nixos-24.05
+    environment:
+      TARGET: "${TARGET}"
+      AWS_ACCESS_KEY_ID:
+        from_secret: garagehq_aws_access_key_id
+      AWS_SECRET_ACCESS_KEY:
+        from_secret: garagehq_aws_secret_access_key
+    commands:
+      - nix-shell --attr ci --run "to_s3"
+
+  - name: docker build and publish
+    image: nixpkgs/nix:nixos-24.05
+    environment:
+      DOCKER_PLATFORM: "linux/${ARCH}"
+      CONTAINER_NAME: "dxflrs/${ARCH}_garage"
+      DOCKER_AUTH:
+        from_secret: docker_auth
+    commands:
+      - mkdir -p /root/.docker
+      - echo $DOCKER_AUTH > /root/.docker/config.json
+      - export CONTAINER_TAG=${CI_COMMIT_TAG:-$CI_COMMIT_SHA}
+      - nix-shell --attr ci --run "to_docker"

Cargo.toml

@@ -3,11 +3,15 @@ resolver = "2"
 members = [
 	"src/db",
 	"src/util",
+	"src/net",
 	"src/rpc",
 	"src/table",
 	"src/block",
 	"src/model",
-	"src/api",
+	"src/api/common",
+	"src/api/s3",
+	"src/api/k2v",
+	"src/api/admin",
 	"src/web",
 	"src/garage",
 	"src/k2v-client",
@@ -17,19 +21,133 @@ members = [
 default-members = ["src/garage"]
 
 [workspace.dependencies]
+
+# Internal Garage crates
 format_table = { version = "0.1.1", path = "src/format-table" }
-garage_api = { version = "0.10.0", path = "src/api" }
+garage_api_common = { version = "1.3.1", path = "src/api/common" }
-garage_block = { version = "0.10.0", path = "src/block" }
+garage_api_admin = { version = "1.3.1", path = "src/api/admin" }
-garage_db = { version = "0.10.0", path = "src/db", default-features = false }
+garage_api_s3 = { version = "1.3.1", path = "src/api/s3" }
-garage_model = { version = "0.10.0", path = "src/model", default-features = false }
+garage_api_k2v = { version = "1.3.1", path = "src/api/k2v" }
-garage_rpc = { version = "0.10.0", path = "src/rpc" }
+garage_block = { version = "1.3.1", path = "src/block" }
-garage_table = { version = "0.10.0", path = "src/table" }
+garage_db = { version = "1.3.1", path = "src/db", default-features = false }
-garage_util = { version = "0.10.0", path = "src/util" }
+garage_model = { version = "1.3.1", path = "src/model", default-features = false }
-garage_web = { version = "0.10.0", path = "src/web" }
+garage_net = { version = "1.3.1", path = "src/net" }
+garage_rpc = { version = "1.3.1", path = "src/rpc" }
+garage_table = { version = "1.3.1", path = "src/table" }
+garage_util = { version = "1.3.1", path = "src/util" }
+garage_web = { version = "1.3.1", path = "src/web" }
 k2v-client = { version = "0.0.4", path = "src/k2v-client" }
 
-[profile.dev]
+# External crates from crates.io
-lto = "off"
+arc-swap = "1.0"
+argon2 = "0.5"
+async-trait = "0.1.7"
+backtrace = "0.3"
+base64 = "0.21"
+blake2 = "0.10"
+bytes = "1.0"
+bytesize = "1.1"
+cfg-if = "1.0"
+chrono = "0.4"
+crc32fast = "1.4"
+crc32c = "0.6"
+crypto-common = "0.1"
+gethostname = "0.4"
+git-version = "0.3.4"
+hex = "0.4"
+hexdump = "0.1"
+hmac = "0.12"
+itertools = "0.12"
+ipnet = "2.9.0"
+lazy_static = "1.4"
+md-5 = "0.10"
+mktemp = "0.5"
+nix = { version = "0.29", default-features = false, features = ["fs"] }
+nom = "7.1"
+parking_lot = "0.12"
+parse_duration = "2.1"
+pin-project = "1.0.12"
+pnet_datalink = "0.34"
+rand = "0.8"
+sha1 = "0.10"
+sha2 = "0.10"
+timeago = { version = "0.4", default-features = false }
+xxhash-rust = { version = "0.8", default-features = false, features = ["xxh3"] }
+
+aes-gcm = { version = "0.10", features = ["aes", "stream"] }
+sodiumoxide = { version = "0.2.5-0", package = "kuska-sodiumoxide" }
+kuska-handshake = { version = "0.2.0", features = ["default", "async_std"] }
+
+clap = { version = "4.1", features = ["derive", "env"] }
+pretty_env_logger = "0.5"
+structopt = { version = "0.3", default-features = false }
+syslog-tracing = "0.3"
+tracing = "0.1"
+tracing-journald = "0.3.1"
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+
+heed = { version = "0.11", default-features = false, features = ["lmdb"] }
+rusqlite = "0.37"
+r2d2 = "0.8"
+r2d2_sqlite = "0.31"
+fjall = "2.4"
+
+async-compression = { version = "0.4", features = ["tokio", "zstd"] }
+zstd = { version = "0.13", default-features = false }
+
+quick-xml = { version = "0.26", features = [ "serialize" ] }
+rmp-serde = "1.1.2"
+serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
+serde_bytes = "0.11"
+serde_json = "1.0"
+toml = { version = "0.8", default-features = false, features = ["parse"] }
+
+# newer version requires rust edition 2021
+k8s-openapi = { version = "0.21", features = ["v1_24"] }
+kube = { version = "0.88", default-features = false, features = ["runtime", "derive", "client", "rustls-tls"] }
+schemars = "0.8"
+reqwest = { version = "0.11", default-features = false, features = ["rustls-tls-manual-roots", "json"] }
+
+form_urlencoded = "1.0.0"
+http = "1.0"
+httpdate = "1.0"
+http-range = "0.1"
+http-body-util = "0.1"
+hyper = { version = "1.0", default-features = false }
+hyper-util = { version = "0.1", features = [ "full" ] }
+multer = "3.0"
+percent-encoding = "2.2"
+roxmltree = "0.19"
+url = "2.3"
+
+futures = "0.3"
+futures-util = "0.3"
+tokio = { version = "1.0", default-features = false, features = ["net", "rt", "rt-multi-thread", "io-util", "net", "time", "macros", "sync", "signal", "fs"] }
+tokio-util = { version = "0.7", features = ["compat", "io"] }
+tokio-stream = { version = "0.1", features = ["net"] }
+
+opentelemetry = { version = "0.17", features = [ "rt-tokio", "metrics", "trace" ] }
+opentelemetry-prometheus = "0.10"
+opentelemetry-otlp = "0.10"
+opentelemetry-contrib = "0.9"
+prometheus = "0.13"
+
+# used by the k2v-client crate only
+aws-sigv4 = { version = "1.1", default-features = false }
+hyper-rustls = { version = "0.26", default-features = false, features = ["http1", "http2", "ring", "rustls-native-certs"] }
+log = "0.4"
+thiserror = "2.0"
+
+# ---- used only as build / dev dependencies ----
+assert-json-diff = "2.0"
+rustc_version = "0.4.0"
+static_init = "1.0"
+aws-smithy-runtime = { version = "1.8", default-features = false, features = ["tls-rustls"] }
+aws-sdk-config = { version = "1.62", default-features = false }
+aws-sdk-s3 = { version = "1.79", default-features = false, features = ["rt-tokio"] }
 
 [profile.release]
-debug = true
+lto = "thin"
+codegen-units = 16
+opt-level = 3
+strip = "debuginfo"

Dockerfile

@@ -3,5 +3,5 @@ FROM scratch
 ENV RUST_BACKTRACE=1
 ENV RUST_LOG=garage=info
 
-COPY result-bin/bin/garage /
+COPY result/bin/garage /
 CMD [ "/garage", "server"]

Makefile

@@ -1,13 +1,8 @@
-.PHONY: doc all release shell run1 run2 run3
+.PHONY: doc all run1 run2 run3
 
 all:
-	clear; cargo build
+	clear
-
+	cargo build
-release:
-	nix-build --attr pkgs.amd64.release --no-build-output
-
-shell:
-	nix-shell
 
 # ----
 

README.md

@@ -1,4 +1,4 @@
-Garage [![Build Status](https://drone.deuxfleurs.fr/api/badges/Deuxfleurs/garage/status.svg?ref=refs/heads/main)](https://drone.deuxfleurs.fr/Deuxfleurs/garage)
+Garage [![status-badge](https://woodpecker.deuxfleurs.fr/api/badges/1/status.svg)](https://woodpecker.deuxfleurs.fr/repos/1)
 ===
 
 <p align="center" style="text-align:center;">

default.nix

@@ -3,54 +3,22 @@
 with import ./nix/common.nix;
 
 let
-  pkgs = import pkgsSrc { };
+  pkgs = import nixpkgs { };
   compile = import ./nix/compile.nix;
 
-  build_debug_and_release = (target: {
+  build_release = target: (compile {
-    debug = (compile {
+    inherit target system git_version nixpkgs;
-      inherit system target git_version pkgsSrc cargo2nixOverlay;
+    crane = flake.inputs.crane;
-      release = false;
+    rust-overlay = flake.inputs.rust-overlay;
-    }).workspace.garage { compileMode = "build"; };
-
-    release = (compile {
-      inherit system target git_version pkgsSrc cargo2nixOverlay;
     release = true;
-    }).workspace.garage { compileMode = "build"; };
+  }).garage;
-  });
-
-  test = (rustPkgs:
-    pkgs.symlinkJoin {
-      name = "garage-tests";
-      paths =
-        builtins.map (key: rustPkgs.workspace.${key} { compileMode = "test"; })
-        (builtins.attrNames rustPkgs.workspace);
-    });
 
 in {
-  pkgs = {
+  releasePackages = {
-    amd64 = build_debug_and_release "x86_64-unknown-linux-musl";
+    amd64 = build_release "x86_64-unknown-linux-musl";
-    i386 = build_debug_and_release "i686-unknown-linux-musl";
+    i386 = build_release "i686-unknown-linux-musl";
-    arm64 = build_debug_and_release "aarch64-unknown-linux-musl";
+    arm64 = build_release "aarch64-unknown-linux-musl";
-    arm = build_debug_and_release "armv6l-unknown-linux-musleabihf";
+    arm = build_release "armv6l-unknown-linux-musleabihf";
-  };
-  test = {
-    amd64 = test (compile {
-      inherit system git_version pkgsSrc cargo2nixOverlay;
-      target = "x86_64-unknown-linux-musl";
-      features = [
-        "garage/bundled-libs"
-        "garage/k2v"
-        "garage/sled"
-        "garage/lmdb"
-        "garage/sqlite"
-      ];
-    });
-  };
-  clippy = {
-    amd64 = (compile {
-      inherit system git_version pkgsSrc cargo2nixOverlay;
-      target = "x86_64-unknown-linux-musl";
-      compiler = "clippy";
-    }).workspace.garage { compileMode = "build"; };
   };
+  flakePackages = flake.packages.${system};
 }

doc/api/garage-admin-v1.yml

@@ -98,7 +98,6 @@ paths:
                       type: string
                     example:
                       - "k2v"
-                      - "sled"
                       - "lmdb"
                       - "sqlite"
                       - "consul-discovery"
@@ -688,7 +687,7 @@ paths:
       operationId: "GetBucketInfo"
       summary: "Get a bucket"
       description: |
-        Given a bucket identifier (`id`) or a global alias (`alias`), get its information.
+        Given a bucket identifier (`id`) or a global alias (`globalAlias`), get its information.
         It includes its aliases, its web configuration, keys that have some permissions
         on it, some statistics (number of objects, size), number of dangling multipart uploads,
         and its quotas (if any).
@@ -702,7 +701,7 @@ paths:
           example: "b4018dc61b27ccb5c64ec1b24f53454bbbd180697c758c4d47a22a8921864a87"
           schema:
             type: string
-        - name: alias
+        - name: globalAlias
           in: query
           description: |
             The exact global alias of one of the existing buckets.

doc/book/build/python.md

@@ -23,7 +23,7 @@ client = minio.Minio(
   "GKyourapikey",
   "abcd[...]1234",
   # Force the region, this is specific to garage
-  region="region",
+  region="garage",
 )
 ```
 

doc/book/connect/apps/index.md

@@ -12,7 +12,7 @@ In this section, we cover the following web applications:
 | [Mastodon](#mastodon)     | ✅       | Natively supported    |
 | [Matrix](#matrix)     | ✅       |  Tested with `synapse-s3-storage-provider`    |
 | [ejabberd](#ejabberd)     | ✅       |  `mod_s3_upload`    |
-| [Pixelfed](#pixelfed)     | ❓       |  Not yet tested    |
+| [Pixelfed](#pixelfed)     | ✅       |  Natively supported    |
 | [Pleroma](#pleroma)     | ❓       |  Not yet tested    |
 | [Lemmy](#lemmy)     | ✅        |  Supported with pict-rs    |
 | [Funkwhale](#funkwhale)     | ❓       | Not yet tested     |
@@ -69,7 +69,7 @@ $CONFIG = array(
         'hostname' => '127.0.0.1', // Can also be a domain name, eg. garage.example.com
         'port' => 3900,            // Put your reverse proxy port or your S3 API port
         'use_ssl' => false,        // Set it to true if you have a TLS enabled reverse proxy
-        'region' => 'garage',      // Garage has only one region named "garage"
+        'region' => 'garage',      // Garage default region is named "garage", edit according to your cluster config
         'use_path_style' => true   // Garage supports only path style, must be set to true
     ],
 ],
@@ -80,6 +80,53 @@ To test your new configuration, just reload your Nextcloud webpage and start sen
 
 *External link:* [Nextcloud Documentation > Primary Storage](https://docs.nextcloud.com/server/latest/admin_manual/configuration_files/primary_storage.html)
 
+#### SSE-C encryption (since Garage v1.0)
+
+Since version 1.0, Garage supports server-side encryption with customer keys
+(SSE-C).  In this mode, Garage is responsible for encrypting and decrypting
+objects, but it does not store the encryption key itself. The encryption key
+should be provided by Nextcloud upon each request.  This mode of operation is
+supported by Nextcloud and it has successfully been tested together with
+Garage.
+
+To enable SSE-C encryption:
+
+1. Make sure your Garage server is accessible via SSL through a reverse proxy
+   such as Nginx, and that it is using a valid public certificate (Nextcloud
+   might be able to connect to an S3 server that is using a self-signed
+   certificate, but you will lose many hours while trying, so don't).
+   Configure values for `use_ssl` and `port` accordingly in your `config.php`
+   file.
+
+2. Generate an encryption key using the following command:
+
+    ```
+    openssl rand -base64 32
+    ```
+
+    Make sure to keep this key **secret**!
+
+3. Add the encryption key in your `config.php` file as follows:
+
+
+    ```php
+    <?php
+    $CONFIG = array(
+    'objectstore' => [
+        'class' => '\\OC\\Files\\ObjectStore\\S3',
+        'arguments' => [
+            ...
+            'sse_c_key' => 'exampleencryptionkeyLbU+5fKYQcVoqnn+RaIOXgo=',
+            ...
+        ],
+    ],
+    ```
+
+Nextcloud will now make Garage encrypt files at rest in the storage bucket.
+These files will not be readable by an S3 client that has credentials to the
+bucket but doesn't also know the secret encryption key.
+
+
 ### External Storage
 
 **From the GUI.** Activate the "External storage support" app from the "Applications" page (click on your account icon on the top right corner of your screen to display the menu). Go to your parameters page (also located below your account icon). Click on external storage (or the corresponding translation in your language).
@@ -88,7 +135,7 @@ To test your new configuration, just reload your Nextcloud webpage and start sen
 *Click on the picture to zoom*
 
 Add a new external storage. Put what you want in "folder name" (eg. "shared"). Select "Amazon S3". Keep "Access Key" for the Authentication field.
-In Configuration, put your bucket name (eg. nextcloud), the host (eg. 127.0.0.1), the port (eg. 3900 or 443), the region (garage). Tick the SSL box if you have put an HTTPS proxy in front of garage. You must tick the "Path access" box and you must leave the "Legacy authentication (v2)" box empty. Put your Key ID (eg. GK...) and your Secret Key in the last two input boxes. Finally click on the tick symbol on the right of your screen.
+In Configuration, put your bucket name (eg. nextcloud), the host (eg. 127.0.0.1), the port (eg. 3900 or 443), the region ("garage" if you use the default, or the one your configured in your `garage.toml`). Tick the SSL box if you have put an HTTPS proxy in front of garage. You must tick the "Path access" box and you must leave the "Legacy authentication (v2)" box empty. Put your Key ID (eg. GK...) and your Secret Key in the last two input boxes. Finally click on the tick symbol on the right of your screen.
 
 Now go to your "Files" app and a new "linked folder" has appeared with the name you chose earlier (eg. "shared").
 
@@ -144,10 +191,10 @@ garage key create peertube-key
 
 Keep the Key ID and the Secret key in a pad, they will be needed later.  
 
-We need two buckets, one for normal videos (named peertube-video) and one for webtorrent videos (named peertube-playlist).
+We need two buckets, one for normal videos (named peertube-videos) and one for webtorrent videos (named peertube-playlists).
 ```bash
-garage bucket create peertube-video
+garage bucket create peertube-videos
-garage bucket create peertube-playlist
+garage bucket create peertube-playlists
 ```
 
 Now we allow our key to read and write on these buckets:
@@ -191,7 +238,7 @@ object_storage:
   # Put localhost only if you have a garage instance running on that node
   endpoint: 'http://localhost:3900' # or "garage.example.com" if you have TLS on port 443
 
-  # Garage supports only one region for now, named garage
+  # Garage default region is named "garage", edit according to your config
   region: 'garage'
 
   credentials:
@@ -206,7 +253,7 @@ object_storage:
     proxify_private_files: false
 
   streaming_playlists:
-    bucket_name: 'peertube-playlist'
+    bucket_name: 'peertube-playlists'
 
     # Keep it empty for our example
     prefix: ''
@@ -216,7 +263,7 @@ object_storage:
 
   # Same settings but for webtorrent videos
   videos:
-    bucket_name: 'peertube-video'
+    bucket_name: 'peertube-videos'
     prefix: ''
     # You must fill this field to make Peertube use our reverse proxy/website logic
     base_url: 'http://peertube-videos.web.garage.localhost'
@@ -245,7 +292,7 @@ with average object size ranging from 50 KB to 150 KB.
 As such, your Garage cluster should be configured appropriately for good performance:
 
 - use Garage v0.8.0 or higher with the [LMDB database engine](@documentation/reference-manual/configuration.md#db-engine-since-v0-8-0).
-  With the default Sled database engine, your database could quickly end up taking tens of GB of disk space.
+  Older versions of Garage used the Sled database engine which had issues, such as databases quickly ending up taking tens of GB of disk space.
 - the Garage database should be stored on a SSD
 
 ### Creating your bucket
@@ -288,6 +335,7 @@ From the [official Mastodon documentation](https://docs.joinmastodon.org/admin/t
 
 ```bash
 $ RAILS_ENV=production bin/tootctl media remove --days 3
+$ RAILS_ENV=production bin/tootctl media remove --days 15 --prune-profiles
 $ RAILS_ENV=production bin/tootctl media remove-orphans
 $ RAILS_ENV=production bin/tootctl preview_cards remove --days 15
 ```
@@ -306,8 +354,6 @@ Imports:	1.7 KB
 Settings:	0 Bytes
 ```
 
-Unfortunately, [old avatars and headers cannot currently be cleaned up](https://github.com/mastodon/mastodon/issues/9567).
-
 ### Migrating your data
 
 Data migration should be done with an efficient S3 client.
@@ -395,7 +441,7 @@ media_storage_providers:
   store_synchronous: True  # do we want to wait that the file has been written before returning?
   config:
     bucket: matrix       # the name of our bucket, we chose matrix earlier
-    region_name: garage  # only "garage" is supported for the region field
+    region_name: garage  # "garage" by default, edit according to your cluster config
     endpoint_url: http://localhost:3900 # the path to the S3 endpoint
     access_key_id: "GKxxx" # your Key ID
     secret_access_key: "xxxx" # your Secret Key

doc/book/connect/backup.md

@@ -55,8 +55,8 @@ Create your key and bucket:
 
 ```bash
 garage key create my-key
-garage bucket create backup
+garage bucket create backups
-garage bucket allow backup --read --write --key my-key
+garage bucket allow backups --read --write --key my-key
 ```
 
 Then register your Key ID and Secret key in your environment:
@@ -161,3 +161,49 @@ kopia repository validate-provider
 
 You can then run all the standard kopia commands: `kopia snapshot create`, `kopia mount`...
 Everything should work out-of-the-box.
+
+## Plakar
+
+Create your key and bucket on Garage server:
+
+```bash
+garage key create my-plakar-key
+garage bucket create plakar-backups
+garage bucket allow plakar-backups --read --write --key my-plakar-key
+…
+```
+
+On Plakar server, add your Garage as a storage location:
+```bash
+plakar store add garageS3 s3://my-garage.tld/plakar-backups \
+region=garage # Or as you've specified in garage.toml \
+access_key=<Key ID from "garage key info my-plakar-key"> \
+secret_access_key=<Secret key from "garage key info my-plakar-key">
+```
+
+Then create the repository.
+```bash
+plakar at @garageS3 create -plaintext # Unencrypted
+# or
+plakar at @garageS3 create #encrypted
+```
+
+If you encrypt your backups (Plakar default), you will need to define a strong passphrase. Do not forget to save your password safely. It will be needed to decrypt your backups.
+
+
+After the repository has been created, check that everything works as expected (that might give an empty result as no file has been added yet, but no error message):
+```bash
+plakar at @garageS3 check
+```
+
+Now that everything is configure, you can use Garage as your backups storage. For instance sync it with a local backup storage:
+```bash
+$ plakar at ~/backups sync to @garageS3
+```
+
+Or list the S3 storage content:
+```bash
+$ plakar at @garageS3 ls
+```
+
+More information in Plakar documentation: https://www.plakar.io/docs/main/quickstart/

doc/book/connect/cli.md

@@ -259,7 +259,7 @@ duck --delete garage:/my-files/an-object.txt
 
 ## WinSCP (libs3) {#winscp}
 
-*You can find instructions on how to use the GUI in french [in our wiki](https://wiki.deuxfleurs.fr/fr/Guide/Garage/WinSCP).*
+*You can find instructions on how to use the GUI in french [in our wiki](https://guide.deuxfleurs.fr/prise_en_main/winscp/).*
 
 How to use `winscp.com`, the CLI interface of WinSCP:
 

doc/book/connect/repositories.md

@@ -17,7 +17,7 @@ Garage can also help you serve this content.
 
 ## Gitea
 
-You can use Garage with Gitea to store your [git LFS](https://git-lfs.github.com/) data, your users' avatar, and their attachements.
+You can use Garage with Gitea to store your [git LFS](https://git-lfs.github.com/) data, your users' avatar, and their attachments.
 You can configure a different target for each data type (check `[lfs]` and `[attachment]` sections of the Gitea documentation) and you can provide a default one through the `[storage]` section.
 
 Let's start by creating a key and a bucket (your key id and secret will be needed later, keep them somewhere):

doc/book/cookbook/ansible.md

@@ -8,18 +8,18 @@ have published Ansible roles.  We list them and compare them below.
 
 ## Comparison of Ansible roles
 
-| Feature                            | [ansible-role-garage](#zorun-ansible-role-garage) | [garage-docker-ansible-deploy](#moan0s-garage-docker-ansible-deploy) |
+| Feature                            | [ansible-role-garage](#zorun-ansible-role-garage) | [garage-docker-ansible-deploy](#moan0s-garage-docker-ansible-deploy) | [eddster ansible-role-garage](#eddster-ansible-role-garage) |
-|------------------------------------|---------------------------------------------|---------------------------------------------------------------|
+|------------------------------------|---------------------------------------------|---------------------------------------------------------------|---------------------------------|
-| **Runtime**                        | Systemd                                     | Docker                                                        |
+| **Runtime**                        | Systemd                                     | Docker                                                        | Systemd                         |
-| **Target OS**                      | Any Linux                                   | Any Linux                                                     |
+| **Target OS**                      | Any Linux                                   | Any Linux                                                     | Any Linux                       |
-| **Architecture**                   | amd64, arm64, i686                          | amd64, arm64                                                  |
+| **Architecture**                   | amd64, arm64, i686                          | amd64, arm64                                                  | arm64, arm, 386, amd64                            |
-| **Additional software**            | None                                        | Traefik                                                       |
+| **Additional software**            | None                                        | Traefik                                                       | Ngnix and Keepalived (optional) |
-| **Automatic node connection**      | ❌                                          | ✅                                                            |
+| **Automatic node connection**      | ❌                                          | ✅                                                            | ✅                              |
-| **Layout management**              | ❌                                          | ✅                                                            |
+| **Layout management**              | ❌                                          | ✅                                                            | ✅                              |
-| **Manage buckets & keys**          | ❌                                          | ✅ (basic)                                                    |
+| **Manage buckets & keys**          | ❌                                          | ✅ (basic)                                                    | ✅                              |
-| **Allow custom Garage config**     | ✅                                          | ❌                                                            |
+| **Allow custom Garage config**     | ✅                                          | ❌                                                            | ❌                              |
-| **Facilitate Garage upgrades**     | ✅                                          | ❌                                                            |
+| **Facilitate Garage upgrades**     | ✅                                          | ❌                                                            | ✅                              |
-| **Multiple instances on one host** | ✅                                          | ✅                                                            |
+| **Multiple instances on one host** | ✅                                          | ✅                                                            | ❌                              |
 
 
 ## zorun/ansible-role-garage
@@ -49,3 +49,15 @@ structured DNS names, etc).
 
 As a result, this role makes it easier to start with Garage on Ansible,
 but is less flexible.
+
+## eddster2309/ansible-role-garage
+
+[Source code](https://github.com/eddster2309/ansible-role-garage), [Ansible galaxy](https://galaxy.ansible.com/ui/standalone/roles/eddster2309/garage/)
+
+This role is a opinionated but customisable role using the official Garage
+static binaries and only requires Systemd. As such it should work on any
+Linux based host. It includes all the nesscary configuration to
+automatically setup a clustered Garage deployment. Most Garage
+configuration options are exposed through Ansible variables so while you
+can't provide a custom config you can get very close. It can optionally
+installed a HA nginx deployment with Keepalived.

doc/book/cookbook/binary-packages.md

@@ -15,9 +15,10 @@ Alpine Linux repositories (available since v3.17):
 apk add garage
 ```
 
-The default configuration file is installed to `/etc/garage.toml`. You can run
+The default configuration file is installed to `/etc/garage/garage.toml`. You can run
-Garage using: `rc-service garage start`. If you don't specify `rpc_secret`, it
+Garage using: `rc-service garage start`.
-will be automatically replaced with a random string on the first start.
+
+If you don't specify `rpc_secret`, it will be automatically replaced with a random string on the first start.
 
 Please note that this package is built without Consul discovery, Kubernetes
 discovery, OpenTelemetry exporter, and K2V features (K2V will be enabled once
@@ -26,7 +27,7 @@ it's stable).
 
 ## Arch Linux
 
-Garage is available in the [AUR](https://aur.archlinux.org/packages/garage).
+Garage is available in the official repositories under [extra](https://archlinux.org/packages/extra/x86_64/garage).
 
 ## FreeBSD
 

doc/book/cookbook/encryption.md

@@ -53,20 +53,43 @@ and that's also why your nodes have super long identifiers.
 
 Adding TLS support built into Garage is not currently planned.
 
-## Garage stores data in plain text on the filesystem
+## Garage stores data in plain text on the filesystem or encrypted using customer keys (SSE-C)
 
-Garage does not handle data encryption at rest by itself, and instead delegates
+For standard S3 API requests, Garage does not encrypt data at rest by itself.
-to the user to add encryption, either at the storage layer (LUKS, etc) or on
+For the most generic at rest encryption of data, we recommend setting up your
-the client side (or both). There are no current plans to add data encryption
+storage partitions on encrypted LUKS devices.
-directly in Garage.
 
-Implementing data encryption directly in Garage might make things simpler for
+If you are developping your own client software that makes use of S3 storage,
-end users, but also raises many more questions, especially around key
+we recommend implementing data encryption directly on the client side and never
-management: for encryption of data, where could Garage get the encryption keys
+transmitting plaintext data to Garage. This makes it easy to use an external
-from ? If we encrypt data but keep the keys in a plaintext file next to them,
+untrusted storage provider if necessary.
-it's useless. We probably don't want to have to manage secrets in garage as it
+
-would be very hard to do in a secure way. Maybe integrate with an external
+Garage does support [SSE-C
-system such as Hashicorp Vault?
+encryption](https://docs.aws.amazon.com/AmazonS3/latest/userguide/ServerSideEncryptionCustomerKeys.html),
+an encryption mode of Amazon S3 where data is encrypted at rest using
+encryption keys given by the client.  The encryption keys are passed to the
+server in a header in each request, to encrypt or decrypt data at the moment of
+reading or writing. The server discards the key as soon as it has finished
+using it for the request.  This mode allows the data to be encrypted at rest by
+Garage itself, but it requires support in the client software. It is also not
+adapted to a model where the server is not trusted or assumed to be
+compromised, as the server can easily know the encryption keys.  Note however
+that when using SSE-C encryption, the only Garage node that knows the
+encryption key passed in a given request is the node to which the request is
+directed (which can be a gateway node), so it is easy to have untrusted nodes
+in the cluster as long as S3 API requests containing SSE-C encryption keys are
+not directed to them.
+
+Implementing automatic data encryption directly in Garage without client-side
+management of keys (something like
+[SSE-S3](https://docs.aws.amazon.com/AmazonS3/latest/userguide/UsingServerSideEncryption.html))
+could make things simpler for end users that don't want to setup LUKS, but also
+raises many more questions, especially around key management: for encryption of
+data, where could Garage get the encryption keys from? If we encrypt data but
+keep the keys in a plaintext file next to them, it's useless. We probably don't
+want to have to manage secrets in Garage as it would be very hard to do in a
+secure way. At the time of speaking, there are no plans to implement this in
+Garage.
 
 
 # Adding data encryption using external tools

doc/book/cookbook/from-source.md

@@ -90,6 +90,6 @@ The following feature flags are available in v0.8.0:
 | `kubernetes-discovery` | optional | Enable automatic registration and discovery<br>of cluster nodes through the Kubernetes API |
 | `metrics` | *by default* | Enable collection of metrics in Prometheus format on the admin API |
 | `telemetry-otlp` | optional | Enable collection of execution traces using OpenTelemetry |
-| `sled` | *by default* | Enable using Sled to store Garage's metadata |
+| `syslog` | optional | Enable logging to Syslog |
-| `lmdb` | optional | Enable using LMDB to store Garage's metadata |
+| `lmdb` | *by default* | Enable using LMDB to store Garage's metadata |
-| `sqlite` | optional | Enable using Sqlite3 to store Garage's metadata |
+| `sqlite` | *by default* | Enable using Sqlite3 to store Garage's metadata |

doc/book/cookbook/kubernetes.md

@@ -11,7 +11,7 @@ Firstly clone the repository:
 
 ```bash
 git clone https://git.deuxfleurs.fr/Deuxfleurs/garage
-cd garage/scripts/helm
+cd garage/script/helm
 ```
 
 Deploy with default options:
@@ -26,6 +26,13 @@ Or deploy with custom values:
 helm install --create-namespace --namespace garage garage ./garage -f values.override.yaml
 ```
 
+If you want to manage the CustomRessourceDefinition used by garage for its `kubernetes_discovery` outside of the helm chart, add `garage.kubernetesSkipCrd: true` to your custom values and use the kustomization before deploying the helm chart:
+
+```bash
+kubectl apply -k ../k8s/crd
+helm install --create-namespace --namespace garage garage ./garage -f values.override.yaml
+```
+
 After deploying, cluster layout must be configured manually as described in [Creating a cluster layout](@/documentation/quick-start/_index.md#creating-a-cluster-layout). Use the following command to access garage CLI:
 
 ```bash
@@ -86,3 +93,62 @@ helm delete --namespace garage garage
 ```
 
 Note that this will leave behind custom CRD `garagenodes.deuxfleurs.fr`, which must be removed manually if desired.
+
+## Increase PVC size on running Garage instances
+
+Since the Garage Helm chart creates the data and meta PVC based on `StatefulSet` templates, increasing the PVC size can be a bit tricky.
+
+### Confirm the `StorageClass` used for Garage supports volume expansion
+
+Confirm the storage class used for garage.
+
+```bash
+kubectl -n garage get pvc 
+NAME            STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS     VOLUMEATTRIBUTESCLASS   AGE
+data-garage-0   Bound    pvc-080360c9-8ce3-4acf-8579-1701e57b7f3f   30Gi       RWO            longhorn-local   <unset>                 77d
+data-garage-1   Bound    pvc-ab8ba697-6030-4fc7-ab3c-0d6df9e3dbc0   30Gi       RWO            longhorn-local   <unset>                 5d8h
+data-garage-2   Bound    pvc-3ab37551-0231-4604-986d-136d0fd950ec   30Gi       RWO            longhorn-local   <unset>                 5d5h
+meta-garage-0   Bound    pvc-3b457302-3023-4169-846e-c928c5f2ea65   3Gi        RWO            longhorn-local   <unset>                 77d
+meta-garage-1   Bound    pvc-49ace2b9-5c85-42df-9247-51c4cf64b460   3Gi        RWO            longhorn-local   <unset>                 5d8h
+meta-garage-2   Bound    pvc-99e2e50f-42b4-4128-ae2f-b52629259723   3Gi        RWO            longhorn-local   <unset>                 5d5h
+```
+
+In this case, the storage class is `longhorn-local`. Now, check if `ALLOWVOLUMEEXPANSION` is true for the used `StorageClass`.
+
+```bash
+kubectl get storageclasses.storage.k8s.io longhorn-local
+NAME             PROVISIONER          RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
+longhorn-local   driver.longhorn.io   Delete          Immediate           true                   103d
+```
+
+If your `StorageClass` does not support volume expansion, double check if you can enable it. Otherwise, your only real option is to spin up a new Garage cluster with increased size and migrate all data over.
+
+If your `StorageClass` supports expansion, you are free to continue.
+
+### Increase the size of the PVCs
+
+Increase the size of all PVCs to your desired size.
+
+```bash
+kubectl -n garage edit pvc data-garage-0
+kubectl -n garage edit pvc data-garage-1
+kubectl -n garage edit pvc data-garage-2
+kubectl -n garage edit pvc meta-garage-0
+kubectl -n garage edit pvc meta-garage-1
+kubectl -n garage edit pvc meta-garage-2
+```
+
+### Increase the size of the `StatefulSet` PVC template
+
+This is an optional step, but if not done, future instances of Garage will be created with the original size from the template.
+
+```bash
+kubectl -n garage delete sts --cascade=orphan garage 
+statefulset.apps "garage" deleted
+```
+
+This will remove the Garage `StatefulSet` but leave the pods running. It may seem destructive but needs to be done this way since edits to the size of PVC templates are prohibited.
+
+### Redeploy the `StatefulSet`
+
+Now the size of future PVCs can be increased, and the Garage Helm chart can be upgraded. The new `StatefulSet` should take ownership of the orphaned pods again.

doc/book/cookbook/monitoring.md

@@ -18,7 +18,7 @@ api_bind_addr = "0.0.0.0:3903"
 ```
 
 This will allow anyone to scrape Prometheus metrics by fetching
-`http://localhost:3093/metrics`. If you want to restrict access
+`http://localhost:3903/metrics`. If you want to restrict access
 to the exported metrics, set the `metrics_token` configuration value
 to a bearer token to be used when fetching the metrics endpoint.
 

doc/book/cookbook/real-world.md

@@ -53,9 +53,9 @@ to store 2 TB of data in total.
 
 ### Best practices
 
-- If you have fast dedicated networking between all your nodes, and are planing to store
+- If you have reasonably fast networking between all your nodes, and are planing to store
-  very large files, bump the `block_size` configuration parameter to 10 MB
+  mostly large files, bump the `block_size` configuration parameter to 10 MB
-  (`block_size = 10485760`).
+  (`block_size = "10M"`).
 
 - Garage stores its files in two locations: it uses a metadata directory to store frequently-accessed
   small metadata items, and a data directory to store data blocks of uploaded objects.
@@ -68,31 +68,42 @@ to store 2 TB of data in total.
   EXT4 is not recommended as it has more strict limitations on the number of inodes,
   which might cause issues with Garage when large numbers of objects are stored.
 
-- If you only have an HDD and no SSD, it's fine to put your metadata alongside the data
-  on the same drive. Having lots of RAM for your kernel to cache the metadata will
-  help a lot with performance.  Make sure to use the LMDB database engine,
-  instead of Sled, which suffers from quite bad performance degradation on HDDs.
-  Sled is still the default for legacy reasons, but is not recommended anymore.
-
-- For the metadata storage, Garage does not do checksumming and integrity
-  verification on its own. If you are afraid of bitrot/data corruption,
-  put your metadata directory on a ZFS or BTRFS partition. Otherwise, just use regular
-  EXT4 or XFS.
-
 - Servers with multiple HDDs are supported natively by Garage without resorting
   to RAID, see [our dedicated documentation page](@/documentation/operations/multi-hdd.md).
 
+- For the metadata storage, Garage does not do checksumming and integrity
+  verification on its own, so it is better to use a robust filesystem such as
+  BTRFS or ZFS. Users have reported that when using the LMDB database engine
+  (the default), database files have a tendency of becoming corrupted after an
+  unclean shutdown (e.g. a power outage), so you should take regular snapshots
+  to be able to recover from such a situation.  This can be done using Garage's
+  built-in automatic snapshotting (since v0.9.4), or by using filesystem level
+  snapshots. If you cannot do so, you might want to switch to Sqlite which is
+  more robust.
+
+- LMDB is the fastest and most tested database engine, but it has the following
+  weaknesses: 1/ data files are not architecture-independent, you cannot simply
+  move a Garage metadata directory between nodes running different architectures,
+  and 2/ LMDB is not suited for 32-bit platforms. Sqlite is a viable alternative
+  if any of these are of concern.
+
+- If you only have an HDD and no SSD, it's fine to put your metadata alongside
+  the data on the same drive, but then consider your filesystem choice wisely
+  (see above). Having lots of RAM for your kernel to cache the metadata will
+  help a lot with performance.  The default LMDB database engine is the most
+  tested and has good performance.
+
 ## Get a Docker image
 
 Our docker image is currently named `dxflrs/garage` and is stored on the [Docker Hub](https://hub.docker.com/r/dxflrs/garage/tags?page=1&ordering=last_updated).
-We encourage you to use a fixed tag (eg. `v0.9.0`) and not the `latest` tag.
+We encourage you to use a fixed tag (eg. `v1.3.0`) and not the `latest` tag.
-For this example, we will use the latest published version at the time of the writing which is `v0.9.0` but it's up to you
+For this example, we will use the latest published version at the time of the writing which is `v1.3.0` but it's up to you
 to check [the most recent versions on the Docker Hub](https://hub.docker.com/r/dxflrs/garage/tags?page=1&ordering=last_updated).
 
 For example:
 
 ```
-sudo docker pull dxflrs/garage:v0.9.0
+sudo docker pull dxflrs/garage:v1.3.0
 ```
 
 ## Deploying and configuring Garage
@@ -115,8 +126,9 @@ A valid `/etc/garage.toml` for our cluster would look as follows:
 metadata_dir = "/var/lib/garage/meta"
 data_dir = "/var/lib/garage/data"
 db_engine = "lmdb"
+metadata_auto_snapshot_interval = "6h"
 
-replication_mode = "3"
+replication_factor = 3
 
 compression_level = 2
 
@@ -140,6 +152,8 @@ Check the following for your configuration files:
 - Make sure `rpc_public_addr` contains the public IP address of the node you are configuring.
   This parameter is optional but recommended: if your nodes have trouble communicating with
   one another, consider adding it.
+  Alternatively, you can also set `rpc_public_addr_subnet`, which can filter
+  the addresses announced to other peers to a specific subnet.
 
 - Make sure `rpc_secret` is the same value on all nodes. It should be a 32-bytes hex-encoded secret key.
   You can generate such a key with `openssl rand -hex 32`.
@@ -157,7 +171,7 @@ docker run \
   -v /etc/garage.toml:/etc/garage.toml \
   -v /var/lib/garage/meta:/var/lib/garage/meta \
   -v /var/lib/garage/data:/var/lib/garage/data \
-  dxflrs/garage:v0.9.0
+  dxflrs/garage:v1.3.0
 ```
 
 With this command line, Garage should be started automatically at each boot.
@@ -171,7 +185,7 @@ If you want to use `docker-compose`, you may use the following `docker-compose.y
 version: "3"
 services:
   garage:
-    image: dxflrs/garage:v0.9.0
+    image: dxflrs/garage:v1.3.0
     network_mode: "host"
     restart: unless-stopped
     volumes:
@@ -187,7 +201,7 @@ upgrades.  With the containerized setup proposed here, the upgrade process
 will require stopping and removing the existing container, and re-creating it
 with the upgraded version.
 
-## Controling the daemon
+## Controlling the daemon
 
 The `garage` binary has two purposes:
   - it acts as a daemon when launched with `garage server`
@@ -245,7 +259,7 @@ You can then instruct nodes to connect to one another as follows:
 Venus$ garage node connect 563e1ac825ee3323aa441e72c26d1030d6d4414aeb3dd25287c531e7fc2bc95d@[fc00:1::1]:3901
 ```
 
-You don't nead to instruct all node to connect to all other nodes:
+You don't need to instruct all node to connect to all other nodes:
 nodes will discover one another transitively.
 
 Now if your run `garage status` on any node, you should have an output that looks as follows:

doc/book/cookbook/reverse-proxy.md

@@ -472,3 +472,32 @@ https:// {
 
 More information on how this endpoint is implemented in Garage is available
 in the [Admin API Reference](@/documentation/reference-manual/admin-api.md) page.
+
+### Fileserver browser
+
+Caddy's built-in
+[file_server](https://caddyserver.com/docs/caddyfile/directives/file_server)
+browser functionality can be extended with the
+[caddy-fs-s3](https://github.com/sagikazarmark/caddy-fs-s3) module.
+
+This can be configured to use Garage as a backend with the following
+configuration:
+
+```caddy
+browse.garage.tld {
+    file_server {
+        fs s3 {
+            bucket test-bucket
+            region garage
+
+            endpoint https://s3.garage.tld
+            use_path_style
+        }
+
+        browse
+    }
+}
+```
+
+Caddy must also be configured with the required `AWS_ACCESS_KEY_ID` and
+`AWS_SECRET_ACCESS_KEY` environment variables to access the bucket.

doc/book/cookbook/systemd.md

@@ -28,6 +28,7 @@ StateDirectory=garage
 DynamicUser=true
 ProtectHome=true
 NoNewPrivileges=true
+LimitNOFILE=42000
 
 [Install]
 WantedBy=multi-user.target

doc/book/design/goals.md

@@ -48,7 +48,22 @@ locations. They use Garage themselves for the following tasks:
 
 - As a backup target using `rclone` and `restic`
 
-- In the Drone continuous integration platform to store task logs
-
 The Deuxfleurs Garage cluster is a multi-site cluster currently composed of
 9 nodes in 3 physical locations.
+
+### Triplebit
+
+[Triplebit](https://www.triplebit.org) is a non-profit hosting provider and
+ISP focused on improving access to privacy-related services. They use
+Garage themselves for the following tasks:
+
+- Hosting of their homepage, [privacyguides.org](https://www.privacyguides.org/), and various other static sites
+
+- As a Mastodon object storage backend for [mstdn.party](https://mstdn.party/) and [mstdn.plus](https://mstdn.plus/)
+
+- As a PeerTube storage backend for [neat.tube](https://neat.tube/)
+
+- As a [Matrix media backend](https://github.com/matrix-org/synapse-s3-storage-provider)
+
+Triplebit's Garage cluster is a multi-site cluster currently composed of
+10 nodes in 3 physical locations.

doc/book/design/internals.md

@@ -97,7 +97,7 @@ delete a tombstone, the following condition has to be met:
   superseeded by the tombstone. This ensures that deleting the tombstone is
   safe and that no deleted value will come back in the system.
 
-Garage makes use of Sled's atomic operations (such as compare-and-swap and
+Garage uses atomic database operations (such as compare-and-swap and
 transactions) to ensure that only tombstones that have been correctly
 propagated to other nodes are ever deleted from the local entry tree.
 

doc/book/design/related-work.md

@@ -67,7 +67,7 @@ Pithos has been abandonned and should probably not used yet, in the following we
 Pithos was relying as a S3 proxy in front of Cassandra (and was working with Scylla DB too).
 From its designers' mouth, storing data in Cassandra has shown its limitations justifying the project abandonment.
 They built a closed-source version 2 that does not store blobs in the database (only metadata) but did not communicate further on it.
-We considered there v2's design but concluded that it does not fit both our *Self-contained & lightweight* and *Simple* properties. It makes the development, the deployment and the operations more complicated while reducing the flexibility.
+We considered their v2's design but concluded that it does not fit both our *Self-contained & lightweight* and *Simple* properties. It makes the development, the deployment and the operations more complicated while reducing the flexibility.
 
 **[Riak CS](https://docs.riak.com/riak/cs/2.1.1/index.html):**
 *Not written yet*

doc/book/development/devenv.md

@@ -36,7 +36,7 @@ sudo killall nix-daemon
 Now you can enter our nix-shell, all the required packages will be downloaded but they will not pollute your environment outside of the shell:
 
 ```bash
-nix-shell
+nix-shell -A devShell
 ```
 
 You can use the traditional Rust development workflow:
@@ -65,8 +65,8 @@ nix-build -j $(nproc) --max-jobs auto
 ```
 
 Our build has multiple parameters you might want to set:
-  - `release` build with release optimisations instead of debug
+  - `release` to build with release optimisations instead of debug
-  - `target allows` for cross compilation
+  - `target` allows for cross compilation
   - `compileMode` can be set to test or bench to build a unit test runner
   - `git_version` to inject the hash to display when running `garage stats`
 
@@ -80,7 +80,7 @@ nix-build \
   --git_version $(git rev-parse HEAD)
 ```
 
-*The result is located in `result/bin`. You can pass arguments to cross compile: check `.drone.yml` for examples.*
+*The result is located in `result/bin`. You can pass arguments to cross compile: check `.woodpecker/release.yml` for examples.*
 
 If you modify a `Cargo.toml` or regenerate any `Cargo.lock`, you must run `cargo2nix`:
 

doc/book/development/miscellaneous-notes.md

@@ -81,12 +81,9 @@ Our cache will be checked.
  - http://www.lpenz.org/articles/nixchannel/index.html
 
 
-## Drone
+## Woodpecker
 
-Do not try to set a build as trusted from the interface or the CLI tool,
+Woodpecker can do parallelism both at the step and the pipeline level. At the step level, parallelism is restricted to the same runner.
-your request would be ignored. Instead, directly edit the database (table `repos`, column `repo_trusted`).
-
-Drone can do parallelism both at the step and the pipeline level. At the step level, parallelism is restricted to the same runner.
 
 ## Building Docker containers
 
@@ -99,3 +96,4 @@ We were:
   - Unable to use the kaniko container provided by Google as we can't run arbitrary logic: we need to put our secret in .docker/config.json.
 
 Finally we chose to build kaniko through nix and use it in a `nix-shell`.
+We then switched to using kaniko from nixpkgs when it was packaged.

doc/book/development/release-process.md

@@ -42,7 +42,7 @@ and the docker containers on Docker Hub.
 
 ## Automation
 
-We automated our release process with Nix and Drone to make it more reliable.
+We automated our release process with Nix and Woodpecker to make it more reliable.
 Here we describe how we have done in case you want to debug or improve it.
 
 ### Caching build steps
@@ -62,52 +62,31 @@ Sending to the cache is done through `nix copy`, for example:
 nix copy --to 's3://nix?endpoint=garage.deuxfleurs.fr&region=garage&secret-key=/etc/nix/signing-key.sec' result
 ```
 
-*Note that you need the signing key. In our case, it is stored as a secret in Drone.*
+*The signing key possessed by the Garage maintainers is required to update the Nix cache.*
 
-The previous command will only send the built packet and not its dependencies.
+The previous command will only send the built package and not its dependencies.
-To send its dependency, a tool named `nix-copy-closure` has been created but it is not compatible with the S3 protocol.
+In the case of our CI pipeline, we want to cache all intermediate build steps
-
+as well. This can be done using this quite involved command (here as an example
-Instead, you can use the following commands to list all the runtime dependencies:
+for the `pkgs.amd64.relase` package):
 
 ```bash
-nix copy \
+nix copy -j8 \
-  --to 's3://nix?endpoint=garage.deuxfleurs.fr&region=garage&secret-key=/etc/nix/signing-key.sec' \
+    --to 's3://nix?endpoint=garage.deuxfleurs.fr&region=garage&secret-key=/etc/nix/nix-signing-key.sec' \
-  $(nix-store -qR result/)
+    $(nix path-info pkgs.amd64.release --file default.nix --derivation --recursive | sed 's/\.drv$/.drv^*/')
 ```
 
-*We could also write this expression with xargs but this tool is not available in our container.*
+This command will simultaneously build all of the required Nix paths (using at
+most 8 parallel Nix builder jobs) and send the resulting objects to the cache.
 
-But in certain cases, we want to cache compile time dependencies also.
+This can be run for all the Garage packages we build using the following command:
-For example, the Nix project does not provide binaries for cross compiling to i686 and thus we need to compile gcc on our own.
-We do not want to compile gcc each time, so even if it is a compile time dependency, we want to cache it.
-
-This time, the command is a bit more involved:
-
-```bash
-nix copy --to \
-  's3://nix?endpoint=garage.deuxfleurs.fr&region=garage&secret-key=/etc/nix/signing-key.sec' \
-   $(nix-store -qR --include-outputs \
-     $(nix-instantiate))
-```
-
-This is the command we use in our CI as we expect the final binary to change, so we mainly focus on
-caching our development dependencies.
-
-*Currently there is no automatic garbage collection of the cache: we should monitor its growth.
-Hopefully, we can erase it totally without breaking any build, the next build will only be slower.*
-
-In practise, we concluded that we do not want to cache all the compilation dependencies.
-Instead, we want to cache the toolchain we use to build Garage each time we change it.
-So we removed from Drone any automatic update of the cache and instead handle them manually with:
 
 ```
 source ~/.awsrc
-nix-shell --run 'refresh_toolchain'
+nix-shell --attr cache --run 'refresh_cache'
 ```
 
-Internally, it will run `nix-build` on  `nix/toolchain.nix` and send the output plus its depedencies to the cache.
+We don't automate this step at each CI build, as *there is currently no automatic garbage collection of the cache.*
-
+This means we should also monitor the cache's size; if it ever becomes too big we can erase it with:
-To erase the cache:
 
 ```
 mc rm --recursive --force 'garage/nix/'
@@ -157,9 +136,9 @@ nix-shell --run refresh_index
 
 If you want to compile for different architectures, you will need to repeat all these commands for each architecture.
 
-**In practise, and except for debugging, you will never directly run these commands. Release is handled by drone**
+**In practice, and except for debugging, you will never directly run these commands. Release is handled by Woodpecker.**
 
-### Drone
+### Drone (obsolete)
 
 Our instance is available at [https://drone.deuxfleurs.fr](https://drone.deuxfleurs.fr).  
 You need an account on [https://git.deuxfleurs.fr](https://git.deuxfleurs.fr) to use it.

doc/book/operations/durability-repairs.md

@@ -19,7 +19,7 @@ connecting to. To run on all nodes, add the `-a` flag as follows:
 
 # Data block operations
 
-## Data store scrub
+## Data store scrub {#scrub}
 
 Scrubbing the data store means examining each individual data block to check that
 their content is correct, by verifying their hash. Any block found to be corrupted
@@ -49,7 +49,7 @@ verifications. Of course, scrubbing the entire data store will also take longer.
 ## Block check and resync
 
 In some cases, nodes hold a reference to a block but do not actually have the block
-stored on disk. Conversely, they may also have on disk blocks that are not referenced
+stored on disk. Conversely, they may also have on-disk blocks that are not referenced
 any more. To fix both cases, a block repair may be run with `garage repair blocks`.
 This will scan the entire block reference counter table to check that the blocks
 exist on disk, and will scan the entire disk store to check that stored blocks
@@ -95,7 +95,7 @@ using the `garage block purge` command.
 
 In [multi-HDD setups](@/documentation/operations/multi-hdd.md), to ensure that
 data blocks are well balanced between storage locations, you may run a
-rebalance operation using `garage repair rebalance`. This is usefull when
+rebalance operation using `garage repair rebalance`. This is useful when
 adding storage locations or when capacities of the storage locations have been
 changed.  Once this is finished, Garage will know for each block of a single
 possible location where it can be, which can increase access speed.  This
@@ -104,6 +104,24 @@ operation will also move out all data from locations marked as read-only.
 
 # Metadata operations
 
+## Metadata snapshotting
+
+It is good practice to setup automatic snapshotting of your metadata database
+file, to recover from situations where it becomes corrupted on disk. This can
+be done at the filesystem level if you are using ZFS or BTRFS.
+
+Since Garage v0.9.4, Garage is able to take snapshots of the metadata database
+itself. This basically amounts to copying the database file, except that it can
+be run live while Garage is running without the risk of corruption or
+inconsistencies.  This can be setup to run automatically on a schedule using
+[`metadata_auto_snapshot_interval`](@/documentation/reference-manual/configuration.md#metadata_auto_snapshot_interval).
+A snapshot can also be triggered manually using the `garage meta snapshot`
+command. Note that taking a snapshot using this method is very intensive as it
+requires making a full copy of the database file, so you might prefer using
+filesystem-level snapshots if possible. To recover a corrupted node from such a
+snapshot, read the instructions
+[here](@/documentation/operations/recovering.md#corrupted_meta).
+
 ## Metadata table resync
 
 Garage automatically resyncs all entries stored in the metadata tables every hour,
@@ -123,4 +141,7 @@ blocks may still be held by Garage. If you suspect that such corruption has occu
 in your cluster, you can run one of the following repair procedures:
 
 - `garage repair versions`: checks that all versions belong to a non-deleted object, and purges any orphan version
-- `garage repair block_refs`: checks that all block references belong to a non-deleted object version, and purges any orphan block reference (this will then allow the blocks to be garbage-collected)
+
+- `garage repair block-refs`: checks that all block references belong to a non-deleted object version, and purges any orphan block reference (this will then allow the blocks to be garbage-collected)
+
+- `garage repair block-rc`: checks that the reference counters for blocks are in sync with the actual number of non-deleted entries in the block reference table

doc/book/operations/layout.md

@@ -12,8 +12,8 @@ An introduction to building cluster layouts can be found in the [production depl
 In Garage, all of the data that can be stored in a given cluster is divided
 into slices which we call *partitions*. Each partition is stored by
 one or several nodes in the cluster
-(see [`replication_mode`](@/documentation/reference-manual/configuration.md#replication_mode)).
+(see [`replication_factor`](@/documentation/reference-manual/configuration.md#replication_factor)).
-The layout determines the correspondence between these partition,
+The layout determines the correspondence between these partitions,
 which exist on a logical level, and actual storage nodes.
 
 ## How cluster layouts work in Garage
@@ -94,10 +94,10 @@ follow the following recommendations:
 ## Understanding unexpected layout calculations
 
 When adding, removing or modifying nodes in a cluster layout, sometimes
-unexpected assigntations of partitions to node can occur. These assignations
+unexpected assignations of partitions to node can occur. These assignations
-are in fact normal and logical, given the objectives of the algorihtm.  Indeed,
+are in fact normal and logical, given the objectives of the algorithm.  Indeed,
-**the layout algorithm prioritizes moving less data between nodes over the fact
+**the layout algorithm prioritizes moving less data between nodes over
-of achieving equal distribution of load. It also tries to use all links between
+achieving equal distribution of load. It also tries to use all links between
 pairs of nodes in equal proportions when moving data.**  This section presents
 two examples and illustrates how one can control Garage's behavior to obtain
 the desired results.
@@ -270,5 +270,5 @@ that is moved to node1).
 This illustrates the second principle of the layout computation: **if there is
 a choice in moving data out of some nodes, then all links between pairs of
 nodes are used in equal proportions** (this is approximately true, there is
-randomness in the algorihtm to achieve this so there might be some small
+randomness in the algorithm to achieve this so there might be some small
 fluctuations, as we see above).

doc/book/operations/multi-hdd.md

@@ -21,14 +21,14 @@ data_dir = [
 ```
 
 Garage will automatically balance all blocks stored by the node
-among the different specified directories, proportionnally to the
+among the different specified directories, proportionally to the
 specified capacities.
 
 ## Updating the list of storage locations
 
 If you add new storage locations to your `data_dir`,
 Garage will not rebalance existing data between storage locations.
-Newly written blocks will be balanced proportionnally to the specified capacities,
+Newly written blocks will be balanced proportionally to the specified capacities,
 and existing data may be moved between drives to improve balancing,
 but only opportunistically when a data block is re-written (e.g. an object
 is re-uploaded, or an object with a duplicate block is uploaded).

doc/book/operations/recovering.md

@@ -5,7 +5,7 @@ weight = 40
 
 Garage is meant to work on old, second-hand hardware.
 In particular, this makes it likely that some of your drives will fail, and some manual intervention will be needed.
-Fear not! For Garage is fully equipped to handle drive failures, in most common cases.
+Fear not! Garage is fully equipped to handle drive failures, in most common cases.
 
 ## A note on availability of Garage
 
@@ -108,3 +108,57 @@ garage layout apply   # once satisfied, apply the changes
 
 Garage will then start synchronizing all required data on the new node.
 This process can be monitored using the `garage stats -a` command.
+
+## Replacement scenario 3: corrupted metadata {#corrupted_meta}
+
+In some cases, your metadata DB file might become corrupted, for instance if
+your node suffered a power outage and did not shut down properly. In this case,
+you can recover without having to change the node ID and rebuilding a cluster
+layout. This means that data blocks will not need to be shuffled around, you
+must simply find a way to repair the metadata file. The best way is generally
+to discard the corrupted file and recover it from another source.
+
+First of all, start by locating the database file in your metadata directory,
+which [depends on your `db_engine`
+choice](@/documentation/reference-manual/configuration.md#db_engine).  Then,
+your recovery options are as follows:
+
+- **Option 1: resyncing from other nodes.** In case your cluster is replicated
+  with two or three copies, you can simply delete the database file, and Garage
+  will resync from other nodes. To do so, stop Garage, delete the database file
+  or directory, and restart Garage. Then, do a full table repair by calling
+  `garage repair -a --yes tables`.  This will take a bit of time to complete as
+  the new node will need to receive copies of the metadata tables from the
+  network.
+
+- **Option 2: restoring a snapshot taken by Garage.** Since v0.9.4, Garage can
+  [automatically take regular
+  snapshots](@/documentation/reference-manual/configuration.md#metadata_auto_snapshot_interval)
+  of your metadata DB file. This file or directory should be located under
+  `<metadata_dir>/snapshots`, and is named according to the UTC time at which it
+  was taken. Stop Garage, discard the database file/directory and replace it by the
+  snapshot you want to use. For instance, in the case of LMDB:
+
+  ```bash
+  cd $METADATA_DIR
+  mv db.lmdb db.lmdb.bak
+  cp -r snapshots/2024-03-15T12:13:52Z db.lmdb
+  ```
+
+  And for Sqlite:
+
+  ```bash
+  cd $METADATA_DIR
+  mv db.sqlite db.sqlite.bak
+  cp snapshots/2024-03-15T12:13:52Z db.sqlite
+  ```
+
+  Then, restart Garage and run a full table repair by calling `garage repair -a
+  --yes tables`.  This should run relatively fast as only the changes that
+  occurred since the snapshot was taken will need to be resynchronized. Of
+  course, if your cluster is not replicated, you will lose all changes that
+  occurred since the snapshot was taken.
+
+- **Option 3: restoring a filesystem-level snapshot.** If you are using ZFS or
+  BTRFS to snapshot your metadata partition, refer to their specific
+  documentation on rolling back or copying files from an old snapshot.

doc/book/operations/upgrading.md

@@ -9,7 +9,7 @@ On a new version release, there is 2 possibilities:
   - protocols and data structures remained the same ➡️ this is a **minor upgrade**
   - protocols or data structures changed  ➡️  this is a **major upgrade**
 
-You can quickly now what type of update you will have to operate by looking at the version identifier:
+You can quickly know what type of update you will have to operate by looking at the version identifier:
 when we require our users to do a major upgrade, we will always bump the first nonzero component of the version identifier
 (e.g. from v0.7.2 to v0.8.0).
 Conversely, for versions that only require a minor upgrade, the first nonzero component will always stay the same (e.g. from v0.8.0 to v0.8.1).
@@ -71,7 +71,19 @@ The entire procedure would look something like this:
 
 2. Take each node offline individually to back up its metadata folder, bring them back online once the backup is done.
   You can do all of the nodes in a single zone at once as that won't impact global cluster availability.
-  Do not try to make a backup of the metadata folder of a running node.
+  Do not try to manually copy the metadata folder of a running node.
+
+  **Since Garage v0.9.4,** you can use the `garage meta snapshot --all` command
+  to take a simultaneous snapshot of the metadata database files of all your
+  nodes.  This avoids the tedious process of having to take them down one by
+  one before upgrading. Be careful that if automatic snapshotting is enabled,
+  Garage only keeps the last two snapshots and deletes older ones, so you might
+  want to disable automatic snapshotting in your upgraded configuration file
+  until you have confirmed that the upgrade ran successfully.  In addition to
+  snapshotting the metadata databases of your nodes, you should back-up at
+  least the `cluster_layout` file of one of your Garage instances (this file
+  should be the same on all nodes and you can copy it safely while Garage is
+  running).
 
 3. Prepare your binaries and configuration files for the new Garage version
 

doc/book/quick-start/_index.md

@@ -42,6 +42,13 @@ If a binary of the last version is not available for your architecture,
 or if you want a build customized for your system,
 you can [build Garage from source](@/documentation/cookbook/from-source.md).
 
+If none of these option work for you, you can also run Garage in a Docker
+container.  When using Docker, the commands used in this guide will not work
+anymore.  We recommend reading the tutorial on [configuring a
+multi-node cluster](@/documentation/cookbook/real-world.md) to learn about
+using Garage as a Docker container. For simplicity, a minimal command to launch
+Garage using Docker is provided in this quick start guide as well.
+
 
 ## Configuring and starting Garage
 
@@ -57,9 +64,9 @@ to generate unique and private secrets for security reasons:
 cat > garage.toml <<EOF
 metadata_dir = "/tmp/meta"
 data_dir = "/tmp/data"
-db_engine = "lmdb"
+db_engine = "sqlite"
 
-replication_mode = "none"
+replication_factor = 1
 
 rpc_bind_addr = "[::]:3901"
 rpc_public_addr = "127.0.0.1:3901"
@@ -79,11 +86,15 @@ index = "index.html"
 api_bind_addr = "[::]:3904"
 
 [admin]
-api_bind_addr = "0.0.0.0:3903"
+api_bind_addr = "[::]:3903"
 admin_token = "$(openssl rand -base64 32)"
+metrics_token = "$(openssl rand -base64 32)"
 EOF
 ```
 
+See the [Configuration file format](https://garagehq.deuxfleurs.fr/documentation/reference-manual/configuration/)
+for complete options and values.
+
 Now that your configuration file has been created, you may save it to the directory of your choice.
 By default, Garage looks for **`/etc/garage.toml`.**
 You can also store it somewhere else, but you will have to specify `-c path/to/garage.toml`
@@ -110,10 +121,31 @@ garage -c path/to/garage.toml server
 
 If you have placed the `garage.toml` file in `/etc` (its default location), you can simply run `garage server`.
 
-You can tune Garage's verbosity as follows (from less verbose to more verbose):
+Alternatively, if you cannot or do not wish to run the Garage binary directly,
+you may use Docker to run Garage in a container using the following command:
 
+```bash
+docker run \
+  -d \
+  --name garaged \
+  -p 3900:3900 -p 3901:3901 -p 3902:3902 -p 3903:3903 \
+  -v /path/to/garage.toml:/etc/garage.toml \
+  -v /path/to/garage/meta:/var/lib/garage/meta \
+  -v /path/to/garage/data:/var/lib/garage/data \
+  dxflrs/garage:v1.3.0
 ```
-RUST_LOG=garage=info garage server
+
+Under Linux, you can substitute `--network host` for `-p 3900:3900 -p 3901:3901 -p 3902:3902 -p 3903:3903`
+
+#### Troubleshooting
+
+Ensure your configuration file, `metadata_dir` and `data_dir`  are readable by the user running the `garage` server or Docker.
+
+You can tune Garage's verbosity by setting the `RUST_LOG=` environment variable. \
+Available log levels are (from less verbose to more verbose): `error`, `warn`, `info` *(default)*, `debug` and `trace`.
+
+```bash
+RUST_LOG=garage=info garage server # default
 RUST_LOG=garage=debug garage server
 RUST_LOG=garage=trace garage server
 ```
@@ -129,6 +161,9 @@ It uses values from the TOML configuration file to find the Garage daemon runnin
 local node, therefore if your configuration file is not at `/etc/garage.toml` you will
 again have to specify `-c path/to/garage.toml` at each invocation.
 
+If you are running Garage in a Docker container, you can set `alias garage="docker exec -ti <container name> /garage"`
+to use the Garage binary inside your container.
+
 If the `garage` CLI is able to correctly detect the parameters of your local Garage node,
 the following command should be enough to show the status of your cluster:
 
@@ -147,11 +182,12 @@ ID                 Hostname  Address         Tag                   Zone  Capacit
 ## Creating a cluster layout
 
 Creating a cluster layout for a Garage deployment means informing Garage
-of the disk space available on each node of the cluster
+of the disk space available on each node of the cluster, `-c`,
-as well as the zone (e.g. datacenter) each machine is located in.
+as well as the name of the zone (e.g. datacenter), `-z`, each machine is located in.
 
-For our test deployment, we are using only one node. The way in which we configure
+For our test deployment, we are have only one node with zone named `dc1` and a
-it does not matter, you can simply write:
+capacity of `1G`, though the capacity is ignored for a single node deployment
+and can be changed later when adding new nodes.
 
 ```bash
 garage layout assign -z dc1 -c 1G <node_id>
@@ -164,7 +200,7 @@ For instance here you could write just `garage layout assign -z dc1 -c 1G 563e`.
 The layout then has to be applied to the cluster, using:
 
 ```bash
-garage layout apply
+garage layout apply --version 1
 ```
 
 
@@ -249,7 +285,7 @@ garage bucket info nextcloud-bucket
 ```
 
 
-## Uploading and downlading from Garage
+## Uploading and downloading from Garage
 
 To download and upload files on garage, we can use a third-party tool named `awscli`.
 
@@ -314,7 +350,7 @@ Check [our s3 compatibility list](@/documentation/reference-manual/s3-compatibil
 
 ### Other tools for interacting with Garage
 
-The following tools can also be used to send and recieve files from/to Garage:
+The following tools can also be used to send and receive files from/to Garage:
 
 - [minio-client](@/documentation/connect/cli.md#minio-client) 
 - [s3cmd](@/documentation/connect/cli.md#s3cmd) 

doc/book/reference-manual/admin-api.md

@@ -8,8 +8,8 @@ listen address is specified in the `[admin]` section of the configuration
 file (see [configuration file
 reference](@/documentation/reference-manual/configuration.md))
 
-**WARNING.** At this point, there is no comittement to stability of the APIs described in this document.
+**WARNING.** At this point, there is no commitment to the stability of the APIs described in this document.
-We will bump the version numbers prefixed to each API endpoint at each time the syntax
+We will bump the version numbers prefixed to each API endpoint each time the syntax
 or semantics change, meaning that code that relies on these endpoint will break
 when changes are introduced.
 
@@ -22,7 +22,7 @@ Versions:
 
 ## Access control
 
-The admin API uses two different tokens for acces control, that are specified in the config file's `[admin]` section:
+The admin API uses two different tokens for access control, that are specified in the config file's `[admin]` section:
 
 - `metrics_token`: the token for accessing the Metrics endpoint (if this token
   is not set in the config file, the Metrics endpoint can be accessed without
@@ -88,8 +88,8 @@ Consult the full health check API endpoint at /v0/health for more details
 
 ### On-demand TLS `GET /check`
 
-To prevent abuses for on-demand TLS, Caddy developpers have specified an endpoint that can be queried by the reverse proxy
+To prevent abuse for on-demand TLS, Caddy developers have specified an endpoint that can be queried by the reverse proxy
-to know if a given domain is allowed to get a certificate. Garage implements this endpoints to tell if a given domain is handled by Garage or is garbage.
+to know if a given domain is allowed to get a certificate. Garage implements these endpoints to tell if a given domain is handled by Garage or is garbage.
 
 Garage responds with the following logic:
  - If the domain matches the pattern `<bucket-name>.<s3_api.root_domain>`, returns 200 OK
@@ -102,7 +102,7 @@ You must manually declare the domain in your reverse-proxy. Idem for K2V.*
 
 *Note 2: buckets in a user's namespace are not supported yet by this endpoint. This is a limitation of this endpoint currently.*
 
-**Example:** Suppose a Garage instance configured with `s3_api.root_domain = .s3.garage.localhost` and `s3_web.root_domain = .web.garage.localhost`.
+**Example:** Suppose a Garage instance is configured with `s3_api.root_domain = .s3.garage.localhost` and `s3_web.root_domain = .web.garage.localhost`.
 
 With a private `media` bucket (name in the global namespace, website is disabled), the endpoint will feature the following behavior:
 

doc/book/reference-manual/configuration.md

@@ -8,34 +8,46 @@ weight = 20
 Here is an example `garage.toml` configuration file that illustrates all of the possible options:
 
 ```toml
-replication_mode = "3"
+replication_factor = 3
+consistency_mode = "consistent"
 
 metadata_dir = "/var/lib/garage/meta"
 data_dir = "/var/lib/garage/data"
+metadata_snapshots_dir = "/var/lib/garage/snapshots"
 metadata_fsync = true
 data_fsync = false
+disable_scrub = false
+use_local_tz = false
+metadata_auto_snapshot_interval = "6h"
 
 db_engine = "lmdb"
 
-block_size = 1048576
+block_size = "1M"
-
+block_ram_buffer_max = "256MiB"
-sled_cache_capacity = "128MiB"
+block_max_concurrent_reads = 16
-sled_flush_every_ms = 2000
+block_max_concurrent_writes_per_request =10
 lmdb_map_size = "1T"
 
 compression_level = 1
 
 rpc_secret = "4425f5c26c5e11581d3223904324dcb5b5d5dfb14e5e7f35e38c595424f5f1e6"
 rpc_bind_addr = "[::]:3901"
+rpc_bind_outgoing = false
 rpc_public_addr = "[fc00:1::1]:3901"
+# or set rpc_public_adr_subnet to filter down autodiscovery to a subnet:
+# rpc_public_addr_subnet = "2001:0db8:f00:b00:/64"
+
+
+allow_world_readable_secrets = false
 
 bootstrap_peers = [
     "563e1ac825ee3323aa441e72c26d1030d6d4414aeb3dd25287c531e7fc2bc95d@[fc00:1::1]:3901",
-    "86f0f26ae4afbd59aaf9cfb059eefac844951efd5b8caeec0d53f4ed6c85f332[fc00:1::2]:3901",
+    "86f0f26ae4afbd59aaf9cfb059eefac844951efd5b8caeec0d53f4ed6c85f332@[fc00:1::2]:3901",
     "681456ab91350f92242e80a531a3ec9392cb7c974f72640112f90a600d7921a4@[fc00:B::1]:3901",
     "212fd62eeaca72c122b45a7f4fa0f55e012aa5e24ac384a72a3016413fa724ff@[fc00:F::1]:3901",
 ]
 
+allow_punycode = false
 
 [consul_discovery]
 api = "catalog"
@@ -65,11 +77,12 @@ root_domain = ".s3.garage"
 [s3_web]
 bind_addr = "[::]:3902"
 root_domain = ".web.garage"
+add_host_to_metrics = true
 
 [admin]
 api_bind_addr = "0.0.0.0:3903"
-metrics_token = "cacce0b2de4bc2d9f5b5fdff551e01ac1496055aed248202d415398987e35f81"
+metrics_token = "BCAdFjoa9G0KJR0WXnHHm7fs1ZAbfpI8iIZ+Z/a2NgI="
-admin_token = "ae8cb40ea7368bbdbb6430af11cca7da833d3458a5f52086f4e805a570fb5c2a"
+admin_token = "UkLeGWEvHnXBqnueR3ISEMWpOnm40jH2tM2HnnL/0F4="
 trace_sink = "http://localhost:4317"
 ```
 
@@ -79,33 +92,44 @@ The following gives details about each available configuration option.
 
 ### Index
 
-Top-level configuration options:
+[Environment variables](#env_variables).
+
+Top-level configuration options, in alphabetical order:
+[`allow_punycode`](#allow_punycode),
+[`allow_world_readable_secrets`](#allow_world_readable_secrets),
+[`block_max_concurrent_reads`](`block_max_concurrent_reads),
+[`block_ram_buffer_max`](#block_ram_buffer_max),
+[`block_max_concurrent_writes_per_request`](#block_max_concurrent_writes_per_request),
 [`block_size`](#block_size),
 [`bootstrap_peers`](#bootstrap_peers),
 [`compression_level`](#compression_level),
-[`data_dir`](#metadata_dir),
+[`consistency_mode`](#consistency_mode),
+[`data_dir`](#data_dir),
 [`data_fsync`](#data_fsync),
 [`db_engine`](#db_engine),
+[`disable_scrub`](#disable_scrub),
 [`lmdb_map_size`](#lmdb_map_size),
+[`metadata_auto_snapshot_interval`](#metadata_auto_snapshot_interval),
 [`metadata_dir`](#metadata_dir),
 [`metadata_fsync`](#metadata_fsync),
-[`replication_mode`](#replication_mode),
+[`metadata_snapshots_dir`](#metadata_snapshots_dir),
+[`replication_factor`](#replication_factor),
 [`rpc_bind_addr`](#rpc_bind_addr),
+[`rpc_bind_outgoing`](#rpc_bind_outgoing),
 [`rpc_public_addr`](#rpc_public_addr),
-[`rpc_secret`](#rpc_secret),
+[`rpc_public_addr_subnet`](#rpc_public_addr_subnet)
-[`rpc_secret_file`](#rpc_secret),
+[`rpc_secret`/`rpc_secret_file`](#rpc_secret),
-[`sled_cache_capacity`](#sled_cache_capacity),
+[`use_local_tz`](#use_local_tz).
-[`sled_flush_every_ms`](#sled_flush_every_ms).
 
 The `[consul_discovery]` section:
 [`api`](#consul_api),
 [`ca_cert`](#consul_ca_cert),
-[`client_cert`](#consul_client_cert),
+[`client_cert`](#consul_client_cert_and_key),
-[`client_key`](#consul_client_cert),
+[`client_key`](#consul_client_cert_and_key),
 [`consul_http_addr`](#consul_http_addr),
-[`meta`](#consul_tags),
+[`meta`](#consul_tags_and_meta),
 [`service_name`](#consul_service_name),
-[`tags`](#consul_tags),
+[`tags`](#consul_tags_and_meta),
 [`tls_skip_verify`](#consul_tls_skip_verify),
 [`token`](#consul_token).
 
@@ -120,25 +144,46 @@ The `[s3_api]` section:
 [`s3_region`](#s3_region).
 
 The `[s3_web]` section:
+[`add_host_to_metrics`](#web_add_host_to_metrics),
 [`bind_addr`](#web_bind_addr),
 [`root_domain`](#web_root_domain).
 
 The `[admin]` section:
 [`api_bind_addr`](#admin_api_bind_addr),
-[`metrics_token`](#admin_metrics_token),
+[`metrics_token`/`metrics_token_file`](#admin_metrics_token),
-[`metrics_token_file`](#admin_metrics_token),
+[`admin_token`/`admin_token_file`](#admin_token),
-[`admin_token`](#admin_token),
-[`admin_token_file`](#admin_token),
 [`trace_sink`](#admin_trace_sink),
 
+### Environment variables {#env_variables}
+
+The following configuration parameters must be specified as environment variables,
+they do not exist in the configuration file:
+
+- `GARAGE_LOG_TO_SYSLOG` (since `v0.9.4`): set this to `1` or `true` to make the
+  Garage daemon send its logs to `syslog` (using the libc `syslog` function)
+  instead of printing to stderr.
+
+- `GARAGE_LOG_TO_JOURNALD` (since `v1.2.0`): set this to `1` or `true` to make the
+  Garage daemon send its logs to `journald` (using the native protocol of `systemd-journald`)
+  instead of printing to stderr.
+
+The following environment variables can be used to override the corresponding
+values in the configuration file:
+
+- [`GARAGE_ALLOW_WORLD_READABLE_SECRETS`](#allow_world_readable_secrets)
+- [`GARAGE_RPC_SECRET` and `GARAGE_RPC_SECRET_FILE`](#rpc_secret)
+- [`GARAGE_ADMIN_TOKEN` and `GARAGE_ADMIN_TOKEN_FILE`](#admin_token)
+- [`GARAGE_METRICS_TOKEN` and `GARAGE_METRICS_TOKEN`](#admin_metrics_token)
+
 
 ### Top-level configuration options
 
-#### `replication_mode` {#replication_mode}
+#### `replication_factor` (since `v1.0.0`) {#replication_factor}
 
-Garage supports the following replication modes:
+The replication factor can be any positive integer smaller or equal the node count in your cluster.
+The chosen replication factor has a big impact on the cluster's failure tolerancy and performance characteristics.
 
-- `none` or `1`: data stored on Garage is stored on a single node. There is no
+- `1`: data stored on Garage is stored on a single node. There is no
   redundancy, and data will be unavailable as soon as one node fails or its
   network is disconnected.  Do not use this for anything else than test
   deployments.
@@ -149,17 +194,6 @@ Garage supports the following replication modes:
   before losing data. Data remains available in read-only mode when one node is
   down, but write operations will fail.
 
-  - `2-dangerous`: a variant of mode `2`, where written objects are written to
-    the second replica asynchronously. This means that Garage will return `200
-    OK` to a PutObject request before the second copy is fully written (or even
-    before it even starts being written).  This means that data can more easily
-    be lost if the node crashes before a second copy can be completed.  This
-    also means that written objects might not be visible immediately in read
-    operations.  In other words, this mode severely breaks the consistency and
-    durability guarantees of standard Garage cluster operation.  Benefits of
-    this mode: you can still write to your cluster when one node is
-    unavailable.
-
 - `3`: data stored on Garage will be stored on three different nodes, if
   possible each in a different zones.  Garage tolerates two node failure, or
   several node failures but in no more than two zones (in a deployment with at
@@ -167,55 +201,84 @@ Garage supports the following replication modes:
   or node failures are only in a single zone, reading and writing data to
   Garage can continue normally.
 
-  - `3-degraded`: a variant of replication mode `3`, that lowers the read
+- `5`, `7`, ...: When setting the replication factor above 3, it is most useful to
-    quorum to `1`, to allow you to read data from your cluster when several
+  choose an uneven value, since for every two copies added, one more node can fail
-    nodes (or nodes in several zones) are unavailable.  In this mode, Garage
+  before losing the ability to write and read to the cluster.
-    does not provide read-after-write consistency anymore.  The write quorum is
-    still 2, ensuring that data successfully written to Garage is stored on at
-    least two nodes.
-
-  - `3-dangerous`: a variant of replication mode `3` that lowers both the read
-    and write quorums to `1`, to allow you to both read and write to your
-    cluster when several nodes (or nodes in several zones) are unavailable.  It
-    is the least consistent mode of operation proposed by Garage, and also one
-    that should probably never be used.
 
 Note that in modes `2` and `3`,
 if at least the same number of zones are available, an arbitrary number of failures in
 any given zone is tolerated as copies of data will be spread over several zones.
 
-**Make sure `replication_mode` is the same in the configuration files of all nodes.
+**Make sure `replication_factor` is the same in the configuration files of all nodes.
 Never run a Garage cluster where that is not the case.**
 
+It is technically possible to change the replication factor although it's a
+dangerous operation that is not officially supported.  This requires you to
+delete the existing cluster layout and create a new layout from scratch,
+meaning that a full rebalancing of your cluster's data will be needed.  To do
+it, shut down your cluster entirely, delete the `custer_layout` files in the
+meta directories of all your nodes, update all your configuration files with
+the new `replication_factor` parameter, restart your cluster, and then create a
+new layout with all the nodes you want to keep.  Rebalancing data will take
+some time, and data might temporarily appear unavailable to your users.
+It is recommended to shut down public access to the cluster while rebalancing
+is in progress.  In theory, no data should be lost as rebalancing is a
+routine operation for Garage, although we cannot guarantee you that everything
+ will go right in such an extreme scenario.
+
+#### `consistency_mode` (since `v1.0.0`) {#consistency_mode}
+
+The consistency mode setting determines the read and write behaviour of your cluster.
+
+  - `consistent`: The default setting. This is what the paragraph above describes.
+    The read and write quorum will be determined so that read-after-write consistency
+    is guaranteed.
+  - `degraded`: Lowers the read
+    quorum to `1`, to allow you to read data from your cluster when several
+    nodes (or nodes in several zones) are unavailable.  In this mode, Garage
+    does not provide read-after-write consistency anymore.
+    The write quorum stays the same as in the `consistent` mode, ensuring that
+    data successfully written to Garage is stored on multiple nodes (depending
+    the replication factor).
+  - `dangerous`: This mode lowers both the read
+    and write quorums to `1`, to allow you to both read and write to your
+    cluster when several nodes (or nodes in several zones) are unavailable.  It
+    is the least consistent mode of operation proposed by Garage, and also one
+    that should probably never be used.
+
+Changing the `consistency_mode` between modes while leaving the `replication_factor` untouched
+(e.g. setting your node's `consistency_mode` to `degraded` when it was previously unset, or from
+`dangerous` to `consistent`), can be done easily by just changing the `consistency_mode`
+parameter in your config files and restarting all your Garage nodes.
+
+The consistency mode can be used together with various replication factors, to achieve
+a wide range of read and write characteristics. Some examples:
+
+  - Replication factor `2`, consistency mode `degraded`: While this mode
+    technically exists, its properties are the same as with consistency mode `consistent`,
+    since the read quorum with replication factor `2`, consistency mode `consistent` is already 1.
+
+  - Replication factor `2`, consistency mode `dangerous`: written objects are written to
+    the second replica asynchronously. This means that Garage will return `200
+    OK` to a PutObject request before the second copy is fully written (or even
+    before it even starts being written).  This means that data can more easily
+    be lost if the node crashes before a second copy can be completed.  This
+    also means that written objects might not be visible immediately in read
+    operations.  In other words, this configuration severely breaks the consistency and
+    durability guarantees of standard Garage cluster operation.  Benefits of
+    this configuration: you can still write to your cluster when one node is
+    unavailable.
+
 The quorums associated with each replication mode are described below:
 
-| `replication_mode` | Number of replicas | Write quorum | Read quorum | Read-after-write consistency? |
+| `consistency_mode` | `replication_factor` | Write quorum | Read quorum | Read-after-write consistency? |
-| ------------------ | ------------------ | ------------ | ----------- | ----------------------------- |
+| ------------------ | -------------------- | ------------ | ----------- | ----------------------------- |
-| `none` or `1`      | 1                  | 1            | 1           | yes                           |
+| `consistent`       | 1                    | 1            | 1           | yes                           |
-| `2`                | 2                  | 2            | 1           | yes                           |
+| `consistent`       | 2                    | 2            | 1           | yes                           |
-| `2-dangerous`      | 2                  | 1            | 1           | NO                            |
+| `dangerous`        | 2                    | 1            | 1           | NO                            |
-| `3`                | 3                  | 2            | 2           | yes                           |
+| `consistent`       | 3                    | 2            | 2           | yes                           |
-| `3-degraded`       | 3                  | 2            | 1           | NO                            |
+| `degraded`         | 3                    | 2            | 1           | NO                            |
-| `3-dangerous`      | 3                  | 1            | 1           | NO                            |
+| `dangerous`        | 3                    | 1            | 1           | NO                            |
-
-Changing the `replication_mode` between modes with the same number of replicas
-(e.g. from `3` to `3-degraded`, or from `2-dangerous` to `2`), can be done easily by
-just changing the `replication_mode` parameter in your config files and restarting all your
-Garage nodes.
-
-It is also technically possible to change the replication mode to a mode with a
-different numbers of replicas, although it's a dangerous operation that is not
-officially supported.  This requires you to delete the existing cluster layout
-and create a new layout from scratch, meaning that a full rebalancing of your
-cluster's data will be needed.  To do it, shut down your cluster entirely,
-delete the `custer_layout` files in the meta directories of all your nodes,
-update all your configuration files with the new `replication_mode` parameter,
-restart your cluster, and then create a new layout with all the nodes you want
-to keep.  Rebalancing data will take some time, and data might temporarily
-appear unavailable to your users.  It is recommended to shut down public access
-to the cluster while rebalancing is in progress.  In theory, no data should be
-lost as rebalancing is a routine operation for Garage, although we cannot
-guarantee you that everything will go right in such an extreme scenario.
 
 #### `metadata_dir` {#metadata_dir}
 
@@ -225,6 +288,7 @@ as the index of all objects, object version and object blocks.
 
 Store this folder on a fast SSD drive if possible to maximize Garage's performance.
 
+
 #### `data_dir` {#data_dir}
 
 The directory in which Garage will store the data blocks of objects.
@@ -245,38 +309,77 @@ data_dir = [
 See [the dedicated documentation page](@/documentation/operations/multi-hdd.md)
 on how to operate Garage in such a setup.
 
+#### `metadata_snapshots_dir` (since `v1.1.0`) {#metadata_snapshots_dir}
+
+The directory in which Garage will store metadata snapshots when it
+performs a snapshot of the metadata database, either when instructed to do
+so from a RPC call or regularly through
+[`metadata_auto_snapshot_interval`](#metadata_auto_snapshot_interval).
+
+By default, Garage will store snapshots into a `snapshots/` subdirectory
+of [`metadata_dir`](#metadata_dir). This might quickly fill up your
+metadata storage space if you use snapshots, because Garage will need up
+to 4x the space of the existing metadata database: each snapshot requires
+roughly as much space as the original database, and Garage temporarily
+needs to store up to three different snapshots before it cleans up the oldest
+snapshot to go back to two stored snapshots.
+
+To prevent filling your disk, you might to change this setting to a
+directory with ample available space, e.g. on the same storage space as
+[`data_dir`](#data_dir).
+
 #### `db_engine` (since `v0.8.0`) {#db_engine}
 
 Since `v0.8.0`, Garage can use alternative storage backends as follows:
 
 | DB engine | `db_engine` value | Database path |
 | --------- | ----------------- | ------------- |
-| [LMDB](https://www.lmdb.tech) (default since `v0.9.0`) | `"lmdb"` | `<metadata_dir>/db.lmdb/` |
+| [LMDB](https://www.symas.com/lmdb) (since `v0.8.0`, default since `v0.9.0`) | `"lmdb"` | `<metadata_dir>/db.lmdb/` |
-| [Sled](https://sled.rs) (default up to `v0.8.0`) | `"sled"` | `<metadata_dir>/db/` |
+| [Sqlite](https://sqlite.org) (since `v0.8.0`) | `"sqlite"` | `<metadata_dir>/db.sqlite` |
-| [Sqlite](https://sqlite.org) | `"sqlite"` | `<metadata_dir>/db.sqlite` |
+| [Fjall](https://github.com/fjall-rs/fjall) (**experimental support** since `v1.3.0`) | `"fjall"` | `<metadata_dir>/db.fjall/` |
+| [Sled](https://sled.rs) (old default, removed since `v1.0`) | `"sled"` | `<metadata_dir>/db/` |
 
-Sled was the only database engine up to Garage v0.7.0. Performance issues and
+Sled was supported until Garage v0.9.x, and was removed in Garage v1.0.
-API limitations of Sled prompted the addition of alternative engines in v0.8.0.
+You can still use an older binary of Garage (e.g. v0.9.4) to migrate
-Since v0.9.0, LMDB is the default engine instead of Sled, and Sled is
+old Sled metadata databases to another engine.
-deprecated. We plan to remove Sled in Garage v1.0.
 
 Performance characteristics of the different DB engines are as follows:
 
-- Sled: tends to produce large data files and also has performance issues,
+- LMDB: the recommended database engine for high-performance distributed clusters.
-  especially when the metadata folder is on a traditional HDD and not on SSD.
+LMDB works very well, but is known to have the following limitations:
 
-- LMDB: the recommended database engine on 64-bit systems, much more
+  - The data format of LMDB is not portable between architectures, so for
-  space-efficient and slightly faster. Note that the data format of LMDB is not
+    instance the Garage database of an x86-64 node cannot be moved to an ARM64
-  portable between architectures, so for instance the Garage database of an
+    node.
-  x86-64 node cannot be moved to an ARM64 node. Also note that, while LMDB can
+
-  technically be used on 32-bit systems, this will limit your node to very
+  - While LMDB can technically be used on 32-bit systems, this will limit your
-  small database sizes due to how LMDB works; it is therefore not recommended.
+    node to very small database sizes due to how LMDB works; it is therefore
+    not recommended.
+
+  - Several users have reported corrupted LMDB database files after an unclean
+    shutdown (e.g. a power outage). This situation can generally be recovered
+    from if your cluster is geo-replicated (by rebuilding your metadata db from
+    other nodes), or if you have saved regular snapshots at the filesystem
+    level.
+
+  - Keys in LMDB are limited to 511 bytes. This limit translates to limits on
+    object keys in S3 and sort keys in K2V that are limted to 479 bytes.
 
 - Sqlite: Garage supports Sqlite as an alternative storage backend for
-  metadata, and although it has not been tested as much, it is expected to work
+  metadata, which does not have the issues listed above for LMDB.
-  satisfactorily.  Since Garage v0.9.0, performance issues have largely been
+  On versions 0.8.x and earlier, Sqlite should be avoided due to abysmal
-  fixed by allowing for a no-fsync mode (see `metadata_fsync`). Sqlite does not
+  performance, which was fixed with the addition of `metadata_fsync`.
-  have the database size limitation of LMDB on 32-bit systems.
+  Sqlite is still probably slower than LMDB due to the way we use it,
+  so it is not the best choice for high-performance storage clusters,
+  but it should work fine in many cases.
+
+- Fjall: a storage engine based on LSM trees, which theoretically allow for
+  higher write throughput than other storage engines that are based on B-trees.
+  Using Fjall could potentially improve Garage's performance significantly in
+  write-heavy workloads. **Support for Fjall is experimental at this point**,
+  we have added it to Garage for evaluation purposes only. **Do not use it for
+  production-critical workloads.**
+
 
 It is possible to convert Garage's metadata directory from one format to another
 using the `garage convert-db` command, which should be used as follows:
@@ -313,9 +416,9 @@ Here is how this option impacts the different database engines:
 
 | Database | `metadata_fsync = false` (default) | `metadata_fsync = true`       |
 |----------|------------------------------------|-------------------------------|
-| Sled     | default options                    | *unsupported*                 |
 | Sqlite   | `PRAGMA synchronous = OFF`         | `PRAGMA synchronous = NORMAL` |
 | LMDB     | `MDB_NOMETASYNC` + `MDB_NOSYNC`    | `MDB_NOMETASYNC`              |
+| Fjall    | default options                    | not supported                 |
 
 Note that the Sqlite database is always ran in `WAL` mode (`PRAGMA journal_mode = WAL`).
 
@@ -332,6 +435,50 @@ at the cost of a moderate drop in write performance.
 Similarly to `metatada_fsync`, this is likely not necessary
 if geographical replication is used.
 
+#### `metadata_auto_snapshot_interval` (since `v0.9.4`) {#metadata_auto_snapshot_interval}
+
+If this value is set, Garage will automatically take a snapshot of the metadata
+DB file at a regular interval and save it in the metadata directory.
+This parameter can take any duration string that can be parsed by
+the [`parse_duration`](https://docs.rs/parse_duration/latest/parse_duration/#syntax) crate.
+
+Snapshots can allow to recover from situations where the metadata DB file is
+corrupted, for instance after an unclean shutdown.  See [this
+page](@/documentation/operations/recovering.md#corrupted_meta) for details.
+Garage keeps only the two most recent snapshots of the metadata DB and deletes
+older ones automatically.
+
+Note that taking a metadata snapshot is a relatively intensive operation as the
+entire data file is copied. A snapshot being taken might have performance
+impacts on the Garage node while it is running. If the cluster is under heavy
+write load when a snapshot operation is running, this might also cause the
+database file to grow in size significantly as pages cannot be recycled easily.
+For this reason, it might be better to use filesystem-level snapshots instead
+if possible.
+
+#### `disable_scrub` {#disable_scrub}
+
+By default, Garage runs a scrub of the data directory approximately once per
+month, with a random delay to avoid all nodes running at the same time.  When
+it scrubs the data directory, Garage will read all of the data files stored on
+disk to check their integrity, and will rebuild any data files that it finds
+corrupted, using the remaining valid copies stored on other nodes.
+See [this page](@/documentation/operations/durability-repairs.md#scrub) for details.
+
+Set the `disable_scrub` configuration value to `true` if you don't need Garage
+to scrub the data directory, for instance if you are already scrubbing at the
+filesystem level. Note that in this case, if you find a corrupted data file,
+you should delete it from the data directory and then call `garage repair
+blocks` on the node to ensure that it re-obtains a copy from another node on
+the network.
+
+#### `use_local_tz` (since `v1.1.0`) {#use_local_tz}
+
+By default, Garage runs the lifecycle worker every day at midnight in UTC. Set the
+`use_local_tz` configuration value to `true` if you want Garage to run the
+lifecycle worker at midnight in your local timezone. If you have multiple nodes,
+you should also ensure that each node has the same timezone configuration.
+
 #### `block_size` {#block_size}
 
 Garage splits stored objects in consecutive chunks of size `block_size`
@@ -347,20 +494,67 @@ files will remain available. This however means that chunks from existing files
 will not be deduplicated with chunks from newly uploaded files, meaning you
 might use more storage space that is optimally possible.
 
-#### `sled_cache_capacity` {#sled_cache_capacity}
+#### `block_ram_buffer_max` (since `v0.9.4`) {#block_ram_buffer_max}
 
-This parameter can be used to tune the capacity of the cache used by
+A limit on the total size of data blocks kept in RAM by S3 API nodes awaiting
-[sled](https://sled.rs), the database Garage uses internally to store metadata.
+to be sent to storage nodes asynchronously.
-Tune this to fit the RAM you wish to make available to your Garage instance.
-This value has a conservative default (128MB) so that Garage doesn't use too much
-RAM by default, but feel free to increase this for higher performance.
 
-#### `sled_flush_every_ms` {#sled_flush_every_ms}
+Explanation: since Garage wants to tolerate node failures, it uses quorum
+writes to send data blocks to storage nodes: try to write the block to three
+nodes, and return ok as soon as two writes complete. So even if all three nodes
+are online, the third write always completes asynchronously.  In general, there
+are not many writes to a cluster, and the third asynchronous write can
+terminate early enough so as to not cause unbounded RAM growth.  However, if
+the S3 API node is continuously receiving large quantities of data and the
+third node is never able to catch up, many data blocks will be kept buffered in
+RAM as they are awaiting transfer to the third node.
 
-This parameters can be used to tune the flushing interval of sled.
+The `block_ram_buffer_max` sets a limit to the size of buffers that can be kept
-Increase this if sled is thrashing your SSD, at the risk of losing more data in case
+in RAM in this process.  When the limit is reached, backpressure is applied
-of a power outage (though this should not matter much as data is replicated on other
+back to the S3 client.
-nodes). The default value, 2000ms, should be appropriate for most use cases.
+
+Note that this only counts buffers that have arrived to a certain stage of
+processing (received from the client + encrypted and/or compressed as
+necessary) and are ready to send to the storage nodes. Many other buffers will
+not be counted and this is not a hard limit on RAM consumption.  In particular,
+if many clients send requests simultaneously with large objects, the RAM
+consumption will always grow linearly with the number of concurrent requests,
+as each request will use a few buffers of size `block_size` for receiving and
+intermediate processing before even trying to send the data to the storage
+node.
+
+The default value is 256MiB.
+
+#### `block_max_concurrent_reads` (since `v1.3.0` / `v2.1.0`) {#block_max_concurrent_reads}
+
+The maximum number of blocks (individual files in the data directory) open
+simultaneously for reading.
+
+Reducing this number does not limit the number of data blocks that can be
+transferred through the network simultaneously. This mechanism was just added
+as a backpressure mechanism for HDD read speed: it helps avoid a situation
+where too many requests are coming in and Garage is reading too many block
+files simultaneously, thus not making timely progress on any of the reads.
+
+When a request to read a data block comes in through the network, the requests
+awaits for one of the `block_max_concurrent_reads` slots to be available
+(internally implemented using a Semaphore object). Once it acquired a read
+slot, it reads the entire block file to RAM and frees the slot as soon as the
+block file is finished reading. Only after the slot is released will the
+block's data start being transferred over the network.  If the request fails to
+acquire a reading slot wihtin 15 seconds, it fails with a timeout error.
+Timeout events can be monitored through the `block_read_semaphore_timeouts`
+metric in Prometheus: a non-zero number of such events indicates an I/O
+bottleneck on HDD read speed.
+
+
+#### `block_max_concurrent_writes_per_request` (since  `v2.1.0`) {#block_max_concurrent_writes_per_request}
+
+This parameter is designed to adapt to the concurrent write performance of 
+different storage media.Maximum number of parallel block writes per put request 
+Higher values improve throughput but increase memory usage.
+
+Default: 3, Recommended: 10-30 for NVMe, 3-10 for HDD
 
 #### `lmdb_map_size` {#lmdb_map_size}
 
@@ -394,7 +588,7 @@ Compression is done synchronously, setting a value too high will add latency to
 This value can be different between nodes, compression is done by the node which receive the
 API call.
 
-#### `rpc_secret`, `rpc_secret_file` or `GARAGE_RPC_SECRET` (env) {#rpc_secret}
+#### `rpc_secret`, `rpc_secret_file` or `GARAGE_RPC_SECRET`, `GARAGE_RPC_SECRET_FILE` (env) {#rpc_secret}
 
 Garage uses a secret key, called an RPC secret, that is shared between all
 nodes of the cluster in order to identify these nodes and allow them to
@@ -406,6 +600,9 @@ Since Garage `v0.8.2`, the RPC secret can also be stored in a file whose path is
 given in the configuration variable `rpc_secret_file`, or specified as an
 environment variable `GARAGE_RPC_SECRET`.
 
+Since Garage `v0.8.5` and `v0.9.1`, you can also specify the path of a file
+storing the secret as the `GARAGE_RPC_SECRET_FILE` environment variable.
+
 #### `rpc_bind_addr` {#rpc_bind_addr}
 
 The address and port on which to bind for inter-cluster communcations
@@ -415,6 +612,17 @@ the node, even in the case of a NAT: the NAT should be configured to forward the
 port number to the same internal port nubmer. This means that if you have several nodes running
 behind a NAT, they should each use a different RPC port number.
 
+#### `rpc_bind_outgoing` (since `v0.9.2`) {#rpc_bind_outgoing}
+
+If enabled, pre-bind all sockets for outgoing connections to the same IP address
+used for listening (the IP address specified in `rpc_bind_addr`) before
+trying to connect to remote nodes.
+This can be necessary if a node has multiple IP addresses,
+but only one is allowed or able to reach the other nodes,
+for instance due to firewall rules or specific routing configuration.
+
+Disabled by default.
+
 #### `rpc_public_addr` {#rpc_public_addr}
 
 The address and port that other nodes need to use to contact this node for
@@ -422,6 +630,14 @@ RPC calls.  **This parameter is optional but recommended.** In case you have
 a NAT that binds the RPC port to a port that is different on your public IP,
 this field might help making it work.
 
+#### `rpc_public_addr_subnet` {#rpc_public_addr_subnet}
+In case `rpc_public_addr` is not set, but autodiscovery is used, this allows
+filtering the list of automatically discovered IPs to a specific subnet.
+
+For example, if nodes should pick *their* IP inside a specific subnet, but you
+don't want to explicitly write the IP down (as it's dynamic, or you want to
+share configs across nodes), you can use this option.
+
 #### `bootstrap_peers` {#bootstrap_peers}
 
 A list of peer identifiers on which to contact other Garage peers of this cluster.
@@ -438,6 +654,24 @@ be obtained by running `garage node id` and then included directly in the
 key will be returned by `garage node id` and you will have to add the IP
 yourself.
 
+#### `allow_world_readable_secrets` or `GARAGE_ALLOW_WORLD_READABLE_SECRETS` (env) {#allow_world_readable_secrets}
+
+Garage checks the permissions of your secret files to make sure they're not
+world-readable. In some cases, the check might fail and consider your files as
+world-readable even if they're not, for instance when using Posix ACLs.
+
+Setting `allow_world_readable_secrets` to `true` bypass this
+permission verification.
+
+Alternatively, you can set the `GARAGE_ALLOW_WORLD_READABLE_SECRETS`
+environment variable to `true` to bypass the permissions check.
+
+#### `allow_punycode` {#allow_punycode}
+
+Allow creating buckets with names containing punycode. When used for buckets served
+as websites, this allows using almost any unicode character in the domain name.
+
+Default to `false`.
 
 ### The `[consul_discovery]` section
 
@@ -460,7 +694,7 @@ the `/v1/catalog` endpoints, enabling mTLS if `client_cert` and `client_key` are
 `service_name` should be set to the service name under which Garage's
 RPC ports are announced.
 
-#### `client_cert`, `client_key` {#consul_client_cert}
+#### `client_cert`, `client_key` {#consul_client_cert_and_key}
 
 TLS client certificate and client key to use when communicating with Consul over TLS. Both are mandatory when doing so.
 Only available when `api = "catalog"`.
@@ -494,7 +728,7 @@ node_prefix "" {
 }
 ```
 
-#### `tags` and `meta` {#consul_tags}
+#### `tags` and `meta` {#consul_tags_and_meta}
 
 Additional list of tags and map of service meta to add during service registration.
 
@@ -569,6 +803,13 @@ For instance, if `root_domain` is `web.garage.eu`, a bucket called `deuxfleurs.f
 will be accessible either with hostname `deuxfleurs.fr.web.garage.eu`
 or with hostname `deuxfleurs.fr`.
 
+#### `add_host_to_metrics` {#web_add_host_to_metrics}
+
+Whether to include the requested domain name (HTTP `Host` header) in the
+Prometheus metrics of the web endpoint. This is disabled by default as the
+number of possible values is not bounded and can be a source of cardinality
+explosion in the exported metrics.
+
 
 ### The `[admin]` section
 
@@ -583,27 +824,29 @@ See [administration API reference](@/documentation/reference-manual/admin-api.md
 Alternatively, since `v0.8.5`, a path can be used to create a unix socket. Note that for security reasons,
 the socket will have 0220 mode. Make sure to set user and group permissions accordingly.
 
-#### `metrics_token`, `metrics_token_file` or `GARAGE_METRICS_TOKEN` (env) {#admin_metrics_token}
+#### `metrics_token`, `metrics_token_file` or `GARAGE_METRICS_TOKEN`, `GARAGE_METRICS_TOKEN_FILE` (env) {#admin_metrics_token}
 
 The token for accessing the Metrics endpoint. If this token is not set, the
 Metrics endpoint can be accessed without access control.
 
-You can use any random string for this value. We recommend generating a random token with `openssl rand -hex 32`.
+You can use any random string for this value. We recommend generating a random token with `openssl rand -base64 32`.
 
 `metrics_token` was introduced in Garage `v0.7.2`.
 `metrics_token_file` and the `GARAGE_METRICS_TOKEN` environment variable are supported since Garage `v0.8.2`.
 
+`GARAGE_METRICS_TOKEN_FILE` is supported since `v0.8.5` / `v0.9.1`.
 
-#### `admin_token`, `admin_token_file` or `GARAGE_ADMIN_TOKEN` (env) {#admin_token}
+#### `admin_token`, `admin_token_file` or `GARAGE_ADMIN_TOKEN`, `GARAGE_ADMIN_TOKEN_FILE` (env) {#admin_token}
 
 The token for accessing all of the other administration endpoints.  If this
 token is not set, access to these endpoints is disabled entirely.
 
-You can use any random string for this value. We recommend generating a random token with `openssl rand -hex 32`.
+You can use any random string for this value. We recommend generating a random token with `openssl rand -base64 32`.
 
 `admin_token` was introduced in Garage `v0.7.2`.
 `admin_token_file` and the `GARAGE_ADMIN_TOKEN` environment variable are supported since Garage `v0.8.2`.
 
+`GARAGE_ADMIN_TOKEN_FILE` is supported since `v0.8.5` / `v0.9.1`.
 
 #### `trace_sink` {#admin_trace_sink}
 

doc/book/reference-manual/features.md

@@ -37,6 +37,21 @@ A Garage cluster can very easily evolve over time, as storage nodes are added or
 Garage will automatically rebalance data between nodes as needed to ensure the desired number of copies.
 Read about cluster layout management [here](@/documentation/operations/layout.md).
 
+### Several replication modes
+
+Garage supports a variety of replication modes, with configurable replica count,
+and with various levels of consistency, in order to adapt to a variety of usage scenarios.
+Read our reference page on [supported replication modes](@/documentation/reference-manual/configuration.md#replication_factor)
+to select the replication mode best suited to your use case (hint: in most cases, `replication_factor = 3` is what you want).
+
+### Compression and deduplication
+
+All data stored in Garage is deduplicated, and optionnally compressed using
+Zstd.  Objects uploaded to Garage are chunked in blocks of constant sizes (see
+[`block_size`](@/documentation/reference-manual/configuration.md#block_size)),
+and the hashes of individual blocks are used to dispatch them to storage nodes
+and to deduplicate them.
+
 ### No RAFT slowing you down
 
 It might seem strange to tout the absence of something as a desirable feature,
@@ -46,14 +61,7 @@ directed to a Garage cluster can be handled independently of one another instead
 of going through a central bottleneck (the leader node).
 As a consequence, requests can be handled much faster, even in cases where latency
 between cluster nodes is important (see our [benchmarks](@/documentation/design/benchmarks/index.md) for data on this).
-This is particularly usefull when nodes are far from one another and talk to one other through standard Internet connections.
+This is particularly useful when nodes are far from one another and talk to one other through standard Internet connections.
-
-### Several replication modes
-
-Garage supports a variety of replication modes, with 1 copy, 2 copies or 3 copies of your data,
-and with various levels of consistency, in order to adapt to a variety of usage scenarios.
-Read our reference page on [supported replication modes](@/documentation/reference-manual/configuration.md#replication_mode)
-to select the replication mode best suited to your use case (hint: in most cases, `replication_mode = "3"` is what you want).
 
 ### Web server for static websites
 

doc/book/reference-manual/monitoring.md

@@ -27,6 +27,112 @@ Exposes the Garage replication factor configured on the node
 garage_replication_factor 3
 ```
 
+#### `garage_local_disk_avail` and `garage_local_disk_total` (gauge)
+
+Reports the available and total disk space on each node, for data and metadata separately.
+
+```
+garage_local_disk_avail{volume="data"} 540341960704
+garage_local_disk_avail{volume="metadata"} 540341960704
+garage_local_disk_total{volume="data"} 763063566336
+garage_local_disk_total{volume="metadata"} 763063566336
+```
+
+### Cluster health status metrics
+
+#### `cluster_healthy` (gauge)
+
+Whether all storage nodes are connected (0 or 1)
+
+```
+cluster_healthy 0
+```
+
+#### `cluster_available` (gauge)
+
+Whether all requests can be served, even if some storage nodes are disconnected
+
+```
+cluster_available 1
+```
+
+#### `cluster_connected_nodes` (gauge)
+
+Number of nodes currently connected
+
+```
+cluster_connected_nodes 3
+```
+
+#### `cluster_known_nodes` (gauge)
+
+Number of nodes already seen once in the cluster
+
+```
+cluster_known_nodes 3
+```
+
+#### `cluster_layout_node_connected` (gauge)
+
+Connection status for individual nodes of the cluster layout
+
+```
+cluster_layout_node_connected{id="62b218d848e86a64",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 1
+cluster_layout_node_connected{id="a11c7cf18af29737",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 0
+cluster_layout_node_connected{id="a235ac7695e0c54d",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 1
+cluster_layout_node_connected{id="b10c110e4e854e5a",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 1
+```
+
+#### `cluster_layout_node_disconnected_time` (gauge)
+
+Time (in seconds) since last connection to individual nodes of the cluster layout
+
+```
+cluster_layout_node_disconnected_time{id="62b218d848e86a64",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 0
+cluster_layout_node_disconnected_time{id="a235ac7695e0c54d",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 0
+cluster_layout_node_disconnected_time{id="b10c110e4e854e5a",role_capacity="1000000000",role_gateway="0",role_zone="dc1"} 0
+```
+
+#### `cluster_storage_nodes` (gauge)
+
+Number of storage nodes declared in the current layout
+
+```
+cluster_storage_nodes 4
+```
+
+#### `cluster_storage_nodes_ok` (gauge)
+
+Number of storage nodes currently connected
+
+```
+cluster_storage_nodes_ok 3
+```
+
+#### `cluster_partitions` (gauge)
+
+Number of partitions in the layout (this is always 256)
+
+```
+cluster_partitions 256
+```
+
+#### `cluster_partitions_all_ok` (gauge)
+
+Number of partitions for which all storage nodes are connected
+
+```
+cluster_partitions_all_ok 64
+```
+
+#### `cluster_partitions_quorum` (gauge)
+
+Number of partitions for which we have a quorum of connected nodes and all requests can be served
+
+```
+cluster_partitions_quorum 256
+```
+
 ### Metrics of the API endpoints
 
 #### `api_admin_request_counter` (counter)
@@ -119,6 +225,17 @@ block_bytes_read 120586322022
 block_bytes_written 3386618077
 ```
 
+#### `block_ram_buffer_free_kb` (gauge)
+
+Kibibytes available for buffering blocks that have to be sent to remote nodes.
+When clients send too much data to this node and a storage node is not receiving
+data fast enough due to slower network conditions, this will decrease down to
+zero and backpressure will be applied.
+
+```
+block_ram_buffer_free_kb 219829
+```
+
 #### `block_compression_level` (counter)
 
 Exposes the block compression level configured for the Garage node.
@@ -275,7 +392,7 @@ table_merkle_updater_todo_queue_length{table_name="block_ref"} 0
 
 #### `table_sync_items_received`, `table_sync_items_sent` (counters)
 
-Number of data items sent to/recieved from other nodes during resync procedures
+Number of data items sent to/received from other nodes during resync procedures
 
 ```
 table_sync_items_received{from="<remote node>",table_name="bucket_v2"} 3

doc/book/reference-manual/s3-compatibility.md

@@ -23,16 +23,17 @@ Feel free to open a PR to suggest fixes this table. Minio is missing because the
 - 2022-05-25 - Many Ceph S3 endpoints are not documented but implemented. Following a notification from the Ceph community, we added them.
 
 
-
 ## High-level features
 
 | Feature                      | Garage                           | [Openstack Swift](https://docs.openstack.org/swift/latest/s3_compat.html) | [Ceph Object Gateway](https://docs.ceph.com/en/latest/radosgw/s3/) | [Riak CS](https://docs.riak.com/riak/cs/2.1.1/references/apis/storage/s3/index.html) | [OpenIO](https://docs.openio.io/latest/source/arch-design/s3_compliancy.html) |
 |------------------------------|----------------------------------|-----------------|---------------|---------|-----|
-| [signature v2](https://docs.aws.amazon.com/general/latest/gr/signature-version-2.html) (deprecated) | ❌ Missing | ✅ |  ✅ | ✅ | ✅ |
+| [signature v2](https://docs.aws.amazon.com/AmazonS3/latest/API/Appendix-Sigv2.html) (deprecated) | ❌ Missing | ✅ |  ✅ | ✅ | ✅ |
 | [signature v4](https://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-authenticating-requests.html) |  ✅ Implemented |  ✅ |  ✅ | ❌ | ✅ |
 | [URL path-style](https://docs.aws.amazon.com/AmazonS3/latest/userguide/VirtualHosting.html#path-style-access) (eg. `host.tld/bucket/key`) |  ✅ Implemented | ✅ |  ✅ | ❓| ✅ |
 | [URL vhost-style](https://docs.aws.amazon.com/AmazonS3/latest/userguide/VirtualHosting.html#virtual-hosted-style-access) URL (eg. `bucket.host.tld/key`) |  ✅ Implemented | ❌| ✅| ✅ | ✅ |
 | [Presigned URLs](https://docs.aws.amazon.com/AmazonS3/latest/userguide/ShareObjectPreSignedURL.html) |  ✅ Implemented | ❌|  ✅ | ✅ |  ✅(❓) |
+| [SSE-C encryption](https://docs.aws.amazon.com/AmazonS3/latest/userguide/ServerSideEncryptionCustomerKeys.html) |  ✅ Implemented | ❓ |  ✅ | ❌ |  ✅ |
+| [Bucket versioning](https://docs.aws.amazon.com/AmazonS3/latest/userguide/Versioning.html) | ❌ Missing | ✅ |  ✅ | ❌ | ✅ |
 
 *Note:* OpenIO does not says if it supports presigned URLs. Because it is part
 of signature v4 and they claim they support it without additional precisions,

doc/book/working-documents/design-draft.md

@@ -42,7 +42,7 @@ The general principle are similar, but details have not been updated.**
 A version is defined by the existence of at least one entry in the blocks table for a certain version UUID.
 We must keep the following invariant: if a version exists in the blocks table, it has to be referenced in the objects table.
 We explicitly manage concurrent versions of an object: the version timestamp and version UUID columns are index columns, thus we may have several concurrent versions of an object.
-Important: before deleting an older version from the objects table, we must make sure that we did a successfull delete of the blocks of that version from the blocks table.
+Important: before deleting an older version from the objects table, we must make sure that we did a successful delete of the blocks of that version from the blocks table.
 
 Thus, the workflow for reading an object is as follows:
 
@@ -95,7 +95,7 @@ Known issue: if someone is reading from a version that we want to delete and the
 Usefull metadata:
 
 - list of versions that reference this block in the Casandra table, so that we can do GC by checking in Cassandra that the lines still exist
-- list of other nodes that we know have acknowledged a write of this block, usefull in the rebalancing algorithm
+- list of other nodes that we know have acknowledged a write of this block, useful in the rebalancing algorithm
 
 Write strategy: have a single thread that does all write IO so that it is serialized (or have several threads that manage independent parts of the hash space). When writing a blob, write it to a temporary file, close, then rename so that a concurrent read gets a consistent result (either not found or found with whole content).
 

doc/book/working-documents/migration-04.md

@@ -68,7 +68,7 @@ The migration steps are as follows:
 5. Turn off Garage 0.3
 
 6. Backup metadata folders if you can (i.e. if you have space to do it
-   somewhere). Backuping data folders could also be usefull but that's much
+   somewhere). Backuping data folders could also be useful but that's much
    harder to do. If your filesystem supports snapshots, this could be a good
    time to use them.
 

doc/book/working-documents/migration-1.md

@@ -0,0 +1,77 @@
++++
+title = "Migrating from 0.9 to 1.0"
+weight = 11
++++
+
+**This guide explains how to migrate to 1.0 if you have an existing 0.9 cluster.
+We don't recommend trying to migrate to 1.0 directly from 0.8 or older.**
+
+This migration procedure has been tested on several clusters without issues.
+However, it is still a *critical procedure* that might cause issues.
+**Make sure to back up all your data before attempting it!**
+
+You might also want to read our [general documentation on upgrading Garage](@/documentation/operations/upgrading.md).
+
+## Changes introduced in v1.0
+
+The following are **breaking changes** in Garage v1.0 that require your attention when migrating:
+
+- The Sled metadata db engine has been **removed**. If your cluster was still
+  using Sled, you will need to **use a Garage v0.9.x binary** to convert the
+  database using the `garage convert-db` subcommand. See
+  [here](@/documentation/reference-manual/configuration.md#db_engine) for the
+  details of the procedure.
+
+The following syntax changes have been made to the configuration file:
+
+- The `replication_mode` parameter has been split into two parameters:
+  [`replication_factor`](@/documentation/reference-manual/configuration.md#replication_factor)
+  and
+  [`consistency_mode`](@/documentation/reference-manual/configuration.md#consistency_mode).
+  The old syntax using `replication_mode` is still supported for legacy
+  reasons and can still be used.
+
+- The parameters `sled_cache_capacity` and `sled_flush_every_ms` have been removed.
+
+## Migration procedure
+
+The migration to Garage v1.0 can be done with almost no downtime,
+by restarting all nodes at once in the new version.
+
+The migration steps are as follows:
+
+1. Do a `garage repair --all-nodes --yes tables`, check the logs and check that
+   all data seems to be synced correctly between nodes. If you have time, do
+   additional `garage repair` procedures (`blocks`, `versions`, `block_refs`,
+   etc.)
+
+2. Ensure you have a snapshot of your Garage installation that you can restore
+   to in case the upgrade goes wrong:
+
+   - If you are running Garage v0.9.4 or later, use the `garage meta snapshot
+     --all` to make a backup snapshot of the metadata directories of your nodes
+     for backup purposes, and save a copy of the following files in the
+     metadata directories of your nodes: `cluster_layout`, `data_layout`,
+     `node_key`, `node_key.pub`.
+
+   - If you are running a filesystem such as ZFS or BTRFS that support
+     snapshotting, you can create a filesystem-level snapshot to be used as a
+     restoration point if needed.
+
+   - In other cases, make a backup using the old procedure: turn off each node
+     individually; back up its metadata folder (for instance, use the following
+     command if your metadata directory is `/var/lib/garage/meta`: `cd
+     /var/lib/garage ; tar -acf meta-v0.9.tar.zst meta/`); turn it back on
+     again.  This will allow you to take a backup of all nodes without
+     impacting global cluster availability.  You can do all nodes of a single
+     zone at once as this does not impact the availability of Garage.
+
+3. Prepare your updated binaries and configuration files for Garage v1.0
+
+4. Shut down all v0.9 nodes simultaneously, and restart them all simultaneously
+   in v1.0.  Use your favorite deployment tool (Ansible, Kubernetes, Nomad) to
+   achieve this as fast as possible.  Garage v1.0 should be in a working state
+   as soon as enough nodes have started.
+
+5. Monitor your cluster in the following hours to see if it works well under
+   your production load.

doc/book/working-documents/testing-strategy.md

@@ -37,7 +37,7 @@ There are two reasons for this:
 
 Reminder: rules of simplicity, concerning changes to Garage's source code.
 Always question what we are doing.
-Never do anything just because it looks nice or because we "think" it might be usefull at some later point but without knowing precisely why/when.
+Never do anything just because it looks nice or because we "think" it might be useful at some later point but without knowing precisely why/when.
 Only do things that make perfect sense in the context of what we currently know.
 
 ## References

doc/drafts/admin-api.md

@@ -8,9 +8,9 @@ listen address is specified in the `[admin]` section of the configuration
 file (see [configuration file
 reference](@/documentation/reference-manual/configuration.md))
 
-**WARNING.** At this point, there is no comittement to stability of the APIs described in this document.
+**WARNING.** At this point, there is no commitment to the stability of the APIs described in this document.
-We will bump the version numbers prefixed to each API endpoint at each time the syntax
+We will bump the version numbers prefixed to each API endpoint each time the syntax
-or semantics change, meaning that code that relies on these endpoint will break
+or semantics change, meaning that code that relies on these endpoints will break
 when changes are introduced.
 
 The Garage administration API was introduced in version 0.7.2, this document
@@ -19,7 +19,7 @@ does not apply to older versions of Garage.
 
 ## Access control
 
-The admin API uses two different tokens for acces control, that are specified in the config file's `[admin]` section:
+The admin API uses two different tokens for access control, that are specified in the config file's `[admin]` section:
 
 - `metrics_token`: the token for accessing the Metrics endpoint (if this token
   is not set in the config file, the Metrics endpoint can be accessed without
@@ -70,10 +70,9 @@ Example response body:
 ```json
 {
   "node": "b10c110e4e854e5aa3f4637681befac755154b20059ec163254ddbfae86b09df",
-  "garageVersion": "v0.10.0",
+  "garageVersion": "v1.3.0",
   "garageFeatures": [
     "k2v",
-    "sled",
     "lmdb",
     "sqlite",
     "metrics",

doc/drafts/k2v-spec.md

@@ -146,7 +146,7 @@ in a bucket, as the partition key becomes the sort key in the index.
 How indexing works:
 
 - Each node keeps a local count of how many items it stores for each partition,
-  in a local Sled tree that is updated atomically when an item is modified.
+  in a local database tree that is updated atomically when an item is modified.
 - These local counters are asynchronously stored in the index table which is
   a regular Garage table spread in the network. Counters are stored as LWW values,
   so basically the final table will have the following structure:
@@ -562,7 +562,7 @@ token>", v: ["<value1>", ...] }`, with the following fields:
 - in case of concurrent update and deletion, a `null` is added to the list of concurrent values
 
 - if the `tombstones` query parameter is set to `true`, tombstones are returned
-  for items that have been deleted (this can be usefull for inserting after an
+  for items that have been deleted (this can be useful for inserting after an
   item that has been deleted, so that the insert is not considered
   concurrent with the delete). Tombstones are returned as tuples in the
   same format with only `null` values

doc/talks/2024-01-12-seed/.gitignore

@@ -0,0 +1,10 @@
+*
+
+!*.txt
+!*.md
+!*.tex
+
+!talk.pdf
+!Makefile
+!.gitignore
+

doc/talks/2024-01-12-seed/Makefile

@@ -0,0 +1,10 @@
+ASSETS=../assets/deuxfleurs.pdf
+
+talk.pdf: talk.tex $(ASSETS)
+	pdflatex talk.tex
+
+assets/%.pdf: assets/%.svg
+	inkscape -D -z --file=$^ --export-pdf=$@
+
+assets/%.pdf_tex: assets/%.svg
+	inkscape -D -z --file=$^ --export-pdf=$@ --export-latex

doc/talks/2024-01-12-seed/talk.tex

@@ -0,0 +1,370 @@
+\nonstopmode
+\documentclass[aspectratio=169]{beamer}
+\usepackage[utf8]{inputenc}
+% \usepackage[frenchb]{babel}
+\usepackage{amsmath}
+\usepackage{mathtools}
+\usepackage{breqn}
+\usepackage{multirow}
+\usetheme{boxes}
+\usepackage{graphicx}
+\usepackage{import}
+\usepackage{adjustbox}
+%\useoutertheme[footline=authortitle,subsection=false]{miniframes}
+%\useoutertheme[footline=authorinstitute,subsection=false]{miniframes}
+\useoutertheme{infolines}
+\setbeamertemplate{headline}{}
+
+\beamertemplatenavigationsymbolsempty
+
+\definecolor{TitleOrange}{RGB}{255,137,0}
+\setbeamercolor{title}{fg=TitleOrange}
+\setbeamercolor{frametitle}{fg=TitleOrange}
+
+\definecolor{ListOrange}{RGB}{255,145,5}
+\setbeamertemplate{itemize item}{\color{ListOrange}$\blacktriangleright$}
+
+\definecolor{verygrey}{RGB}{70,70,70}
+\setbeamercolor{normal text}{fg=verygrey}
+
+
+\usepackage{tabu}
+\usepackage{multicol}
+\usepackage{vwcol}
+\usepackage{stmaryrd}
+\usepackage{graphicx}
+
+\usepackage[normalem]{ulem}
+
+\AtBeginSection[]{
+  \begin{frame}
+  \vfill
+  \centering
+  \begin{beamercolorbox}[sep=8pt,center,shadow=true,rounded=true]{title}
+    \usebeamerfont{title}\insertsectionhead\par%
+  \end{beamercolorbox}
+  \vfill
+  \end{frame}
+}
+
+\title{Garage}
+\subtitle{a lightweight and robust geo-distributed data storage system}
+\author{Alex Auvolat, Deuxfleurs}
+\date{SEED webinar, 2024-01-12}
+
+\begin{document}
+
+% \begin{frame}
+% 	\centering
+% 	\includegraphics[width=.3\linewidth]{../../sticker/Garage.png}
+% 	\vspace{1em}
+% 
+% 	{\large\bf Alex Auvolat, Deuxfleurs Association}
+% 	\vspace{1em}
+% 
+% 	\url{https://garagehq.deuxfleurs.fr/}
+% 
+% 	%Matrix channel: \texttt{\#garage:deuxfleurs.fr}
+% \end{frame}
+
+\begin{frame}
+	%\frametitle{Who I am}
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.4\linewidth, valign=t]{../assets/alex.jpg}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Alex Auvolat}\\
+			Member of Deuxfleurs, lead developer of Garage
+		\end{column}
+		\begin{column}{.2\textwidth}
+			~
+		\end{column}
+	\end{columns}
+	\vspace{.5em}
+
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.6\linewidth, valign=t]{../../logo/garage-notext.png}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\\\textbf{Garage}\\
+			A self-hosted alternative to S3 for object storage
+		\end{column}
+		\begin{column}{.2\textwidth}
+			~
+		\end{column}
+	\end{columns}
+	\vspace{2em}
+
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.5\linewidth, valign=t]{../assets/deuxfleurs.pdf}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Deuxfleurs}\\
+			A non-profit self-hosting collective,\\
+			member of the CHATONS network
+		\end{column}
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.7\linewidth, valign=t]{../assets/logo_chatons.png}
+		\end{column}
+	\end{columns}
+
+\end{frame}
+
+\begin{frame}
+	\frametitle{Stable vs Resilient}
+
+	\hspace{1em}
+	\begin{minipage}{7cm}
+		\textbf{Building a "stable" system:}
+		\vspace{1em}
+
+		Enterprise-grade systems typically employ:
+		\vspace{1em}
+		\begin{itemize}
+			\item RAID
+			\item Redundant power grid + UPS
+			\item Redundant Internet connections
+			\item Low-latency links
+			\item ... 
+		\end{itemize}
+		\vspace{1em}
+		$\to$ costly, only worth at DC scale\\
+		$\to$ still risk of DC-level incident...
+	\end{minipage}
+	\hfill
+	\begin{minipage}{7cm}
+		\textbf{Building a \underline{resilient} system:}
+		\vspace{1em}
+
+		An alternative, cheaper way:
+		\vspace{1em}
+		\begin{itemize}
+			\item Commodity hardware \\(e.g. old desktop PCs)
+				\vspace{.5em}
+			\item Commodity Internet \\(e.g. FTTB, FTTH) and power grid
+				\vspace{.5em}
+			\item \textbf{Geographical redundancy} \\(multi-site replication)
+		\end{itemize}
+		\vspace{1.5em}
+	\end{minipage}
+	\hspace{1em}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Example: our infrastructure at Deuxfleurs}
+	\only<1>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/neptune.jpg}
+		\end{center}
+	}
+	\only<2>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/atuin.jpg}
+		\end{center}
+	}
+	\only<3>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/inframap_jdll2023.pdf}
+		\end{center}
+	}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Object storage: simpler than file systems}
+
+	\begin{minipage}{6cm}
+		Only two operations:
+		\vspace{1em}
+		\begin{itemize}
+			\item Put an object at a key
+				\vspace{1em}
+			\item Retrieve an object from its key
+		\end{itemize}
+		\vspace{1em}
+		{\footnotesize (and a few others)}
+
+		\vspace{1em}
+		Sufficient for many applications!
+	\end{minipage}
+	\hfill
+	\begin{minipage}{8cm}
+		\begin{center}
+			\vspace{2em}
+			\includegraphics[height=6em]{../2020-12-02_wide-team/img/Amazon-S3.jpg}
+			\hspace{2em}
+			\includegraphics[height=5em]{../assets/minio.png}
+
+			\vspace{2em}
+			\includegraphics[height=6em]{../../logo/garage_hires_crop.png}
+		\end{center}
+		\vspace{1em}
+	\end{minipage}
+\end{frame}
+
+
+\begin{frame}
+	\frametitle{The data model of object storage}
+	Object storage is basically a key-value store:
+	\vspace{1em}
+
+		\begin{center}
+		\begin{tabular}{|l|p{8cm}|}
+			\hline
+			\textbf{Key: file path + name} & \textbf{Value: file data + metadata} \\
+			\hline
+			\hline
+			\texttt{index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 24929} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{img/logo.svg} &
+				\texttt{Content-Type: text/svg+xml} \newline
+				\texttt{Content-Length: 13429} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{download/index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 26563} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+		\end{tabular}
+		\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Implementation: consensus vs weak consistency}
+
+	\hspace{1em}
+	\begin{minipage}{7cm}
+		\textbf{Consensus-based systems:}
+		\vspace{1em}
+		\begin{itemize}
+			\item \textbf{Leader-based:} a leader is elected to coordinate
+				all reads and writes
+				\vspace{1em}
+			\item Allows for \textbf{sequential reasoning}:
+				program as if running on a single machine
+				\vspace{1em}
+			\item Serializability is one of the \\
+				\textbf{strongest consistency guarantees}
+				\vspace{1em}
+			\item \textbf{Costly}, the leader is a bottleneck;
+				leader elections on failure take time
+		\end{itemize}
+	\end{minipage}
+	\hfill
+	\begin{minipage}{7cm} \visible<2->{
+		\textbf{Weakly consistent systems:}
+		\vspace{1em}
+		\begin{itemize}
+			\item \textbf{Nodes are equivalent}, any node
+				can originate a read or write operation
+				\vspace{1em}
+			\item \textbf{Operations must be independent},
+				conflicts are resolved after the fact
+				\vspace{1em}
+			\item Strongest achievable consistency:\\
+				\textbf{read-after-write consistency}\\(using quorums)
+				\vspace{1em}
+			\item \textbf{Fast}, no single bottleneck;\\
+				works transparently with offline nodes
+		\end{itemize}
+	} \end{minipage}
+	\hspace{1em}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Why avoid consensus?}
+	Consensus can be implemented reasonably well in practice, so why avoid it?
+	\vspace{2em}
+	\begin{itemize}
+		\item \textbf{Software complexity:} RAFT and PAXOS are complex beasts;\\
+			harder to prove, harder to reason about
+			\vspace{1.5em}
+		\item \textbf{Performance issues:}
+			\vspace{1em}
+			\begin{itemize}
+				\item Taking a decision may take an \textbf{arbitrary number of steps} (in adverse scenarios)
+					\vspace{1em}
+				\item The leader is a \textbf{bottleneck} for all requests;\\
+					even in leaderless approaches, \textbf{all nodes must process all operations in order}
+					\vspace{1em}
+				\item Particularly \textbf{sensitive to higher latency} between nodes
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Objective: the right level of consistency for Garage}
+
+	\underline{Constraints:} slow network (geographical distance), node unavailability/crashes\\
+	\underline{Objective:} maximize availability, maintain an \emph{appropriate level of consistency}\\
+	\vspace{1em}
+	\begin{enumerate}
+		\item<2-> \textbf{Weak consistency for most things}\\
+			\vspace{1em}
+			\underline{Example:} \texttt{PutObject}\\
+			\vspace{.5em}
+			If two clients write the same
+			object at the same time, one of the two is implicitly overwritten.
+			No need to coordinate, use a \emph{last-writer-wins register}.
+			\vspace{1em}
+		\item<3-> \textbf{Stronger consistency only when necessary}\\
+			\vspace{1em}
+			\underline{Example:} \texttt{CreateBucket}\\
+			\vspace{.5em}
+			A bucket is a reserved name in a shared namespace,
+			two clients should be prevented from both creating the same bucket
+			(\emph{mutual exclusion}).
+	\end{enumerate}
+\end{frame}
+
+\begin{frame}
+	\frametitle{The possibility of \emph{leaderless consensus}}
+	Currently, Garage \emph{only has weak consistency}. Is fast, but \texttt{CreateBucket} is broken!
+
+	\visible<2->{
+		\vspace{1em}
+		Leaderless consensus (Antoniadis et al., 2023) alleviates issues with RAFT and PAXOS:
+			\vspace{1em}
+		\begin{itemize}
+			\item \textbf{No leader.} All nodes participate equally at each time step,
+				and different nodes can be unavailable at different times without issues.
+				\\ \vspace{.5em} $\to$ better tolerance to the high latency (remove bottleneck issue)
+				\\ $\to$ tolerates crash transparently
+				\vspace{1em}
+			\item \textbf{Simpler formalization.} The algorithm is very simple to express and to analyze in mathematical terms.
+		\end{itemize}
+	}
+	\visible<3->{
+		\vspace{1em}
+		One of the possible subjects for this PhD:
+		\\$\to$ \emph{integration of leaderless consensus in Garage} + testing + perf eval, etc.
+	}
+\end{frame}
+
+\begin{frame}
+	\begin{center}
+			\includegraphics[width=.25\linewidth]{../../logo/garage_hires.png}\\
+			\vspace{-1em}
+		\url{https://garagehq.deuxfleurs.fr/}\\
+		\url{mailto:garagehq@deuxfleurs.fr}\\
+		\texttt{\#garage:deuxfleurs.fr} on Matrix
+
+		\vspace{1.5em}
+			\includegraphics[width=.06\linewidth]{../assets/rust_logo.png}
+			\includegraphics[width=.13\linewidth]{../assets/AGPLv3_Logo.png}
+	\end{center}
+\end{frame}
+
+\end{document}
+
+%% vim: set ts=4 sw=4 tw=0 noet spelllang=en :

doc/talks/2024-02-03-fosdem/.gitignore

@@ -0,0 +1,17 @@
+*
+
+!*.txt
+!*.md
+
+!assets
+
+!.gitignore
+!*.svg
+!*.png
+!*.jpg
+!*.tex
+!Makefile
+!.gitignore
+!assets/*.drawio.pdf
+
+!talk.pdf

doc/talks/2024-02-03-fosdem/Makefile

@@ -0,0 +1,19 @@
+ASSETS=../assets/lattice/lattice1.pdf_tex \
+	   ../assets/lattice/lattice2.pdf_tex \
+	   ../assets/lattice/lattice3.pdf_tex \
+	   ../assets/lattice/lattice4.pdf_tex \
+	   ../assets/lattice/lattice5.pdf_tex \
+	   ../assets/lattice/lattice6.pdf_tex \
+	   ../assets/lattice/lattice7.pdf_tex \
+	   ../assets/lattice/lattice8.pdf_tex \
+	   ../assets/logos/deuxfleurs.pdf \
+	   ../assets/timeline-22-24.pdf
+
+talk.pdf: talk.tex $(ASSETS)
+	pdflatex talk.tex
+
+%.pdf: %.svg
+	inkscape -D -z --file=$^ --export-pdf=$@
+
+%.pdf_tex: %.svg
+	inkscape -D -z --file=$^ --export-pdf=$@ --export-latex

doc/talks/2024-02-03-fosdem/talk.tex

@@ -0,0 +1,764 @@
+\nonstopmode
+\documentclass[aspectratio=169,xcolor={svgnames}]{beamer}
+\usepackage[utf8]{inputenc}
+% \usepackage[frenchb]{babel}
+\usepackage{amsmath}
+\usepackage{mathtools}
+\usepackage{breqn}
+\usepackage{multirow}
+\usetheme{boxes}
+\usepackage{graphicx}
+\usepackage{import}
+\usepackage{adjustbox}
+\usepackage[absolute,overlay]{textpos}
+%\useoutertheme[footline=authortitle,subsection=false]{miniframes}
+%\useoutertheme[footline=authorinstitute,subsection=false]{miniframes}
+\useoutertheme{infolines}
+\setbeamertemplate{headline}{}
+
+\beamertemplatenavigationsymbolsempty
+
+\definecolor{TitleOrange}{RGB}{255,137,0}
+\setbeamercolor{title}{fg=TitleOrange}
+\setbeamercolor{frametitle}{fg=TitleOrange}
+
+\definecolor{ListOrange}{RGB}{255,145,5}
+\setbeamertemplate{itemize item}{\color{ListOrange}$\blacktriangleright$}
+
+\definecolor{verygrey}{RGB}{70,70,70}
+\setbeamercolor{normal text}{fg=verygrey}
+
+
+\usepackage{tabu}
+\usepackage{multicol}
+\usepackage{vwcol}
+\usepackage{stmaryrd}
+\usepackage{graphicx}
+
+\usepackage[normalem]{ulem}
+
+\AtBeginSection[]{
+  \begin{frame}
+  \vfill
+  \centering
+  \begin{beamercolorbox}[sep=8pt,center,shadow=true,rounded=true]{title}
+    \usebeamerfont{title}\insertsectionhead\par%
+  \end{beamercolorbox}
+  \vfill
+  \end{frame}
+}
+
+\title{Garage, the low-tech storage platform for geo-distributed clusters}
+\author{Alex Auvolat, Deuxfleurs}
+\date{FOSDEM'24, 2024-02-03}
+
+\begin{document}
+
+\begin{frame}
+	\centering
+	\includegraphics[width=.3\linewidth]{../../sticker/Garage.png}
+	\vspace{1em}
+
+	{\large\bf Alex Auvolat, Deuxfleurs Association}
+	\vspace{1em}
+
+	\url{https://garagehq.deuxfleurs.fr/}
+
+	Matrix channel: \texttt{\#garage:deuxfleurs.fr}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Who I am}
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.4\linewidth, valign=t]{../assets/alex.jpg}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Alex Auvolat}\\
+			PhD; co-founder of Deuxfleurs
+		\end{column}
+		\begin{column}{.2\textwidth}
+			~
+		\end{column}
+	\end{columns}
+	\vspace{2em}
+
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.5\linewidth, valign=t]{../assets/logos/deuxfleurs.pdf}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Deuxfleurs}\\
+			A non-profit self-hosting collective,\\
+			member of the CHATONS network
+		\end{column}
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.7\linewidth, valign=t]{../assets/logos/logo_chatons.png}
+		\end{column}
+	\end{columns}
+
+\end{frame}
+
+\begin{frame}
+	\frametitle{Our objective at Deuxfleurs}
+	
+	\begin{center}
+		\textbf{Promote self-hosting and small-scale hosting\\
+			as an alternative to large cloud providers}
+	\end{center}
+	\vspace{2em}
+	\visible<2->{
+		Why is it hard?
+	}
+	\visible<3->{
+		\vspace{2em}
+		\begin{center}
+			\textbf{\underline{Resilience}}\\
+			{\footnotesize we want good uptime/availability with low supervision}
+		\end{center}
+	}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Building a resilient system with cheap stuff}
+
+	\only<1,4-7>{
+		\begin{itemize}
+			\item \textcolor<5->{gray}{Commodity hardware (e.g. old desktop PCs)\\
+				\vspace{.5em}
+				\visible<4->{{\footnotesize (can die at any time)}}}
+				\vspace{1.5em}
+			\item<5-> \textcolor<7->{gray}{Regular Internet (e.g. FTTB, FTTH) and power grid connections\\
+				\vspace{.5em}
+				\visible<6->{{\footnotesize (can be unavailable randomly)}}}
+				\vspace{1.5em}
+			\item<7-> \textbf{Geographical redundancy} (multi-site replication)
+		\end{itemize}
+	}
+	\only<2>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/neptune.jpg}
+		\end{center}
+	}
+	\only<3>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/atuin.jpg}
+		\end{center}
+	}
+	\only<8>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/inframap_jdll2023.pdf}
+		\end{center}
+	}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Object storage: a crucial component}
+		\begin{center}
+			\includegraphics[height=6em]{../assets/logos/Amazon-S3.jpg}
+			\hspace{3em}
+			\visible<2->{\includegraphics[height=5em]{../assets/logos/minio.png}}
+			\hspace{3em}
+			\visible<3>{\includegraphics[height=6em]{../../logo/garage_hires_crop.png}}
+		\end{center}
+		\vspace{1em}
+	S3: a de-facto standard, many compatible applications
+
+	\vspace{1em}
+	\visible<2->{MinIO is self-hostable but not suited for geo-distributed deployments}
+
+	\vspace{1em}
+	\visible<3->{\textbf{Garage is a self-hosted drop-in replacement for the Amazon S3 object store}}
+\end{frame}
+
+\begin{frame}
+	\frametitle{CRDTs / weak consistency instead of consensus}
+
+	\underline{Internally, Garage uses only CRDTs} (conflict-free replicated data types)
+
+	\vspace{2em}
+	Why not Raft, Paxos, ...? Issues of consensus algorithms:
+
+	\vspace{1em}
+	\begin{itemize}
+		\item<2-> \textbf{Software complexity}
+			\vspace{1em}
+		\item<3-> \textbf{Performance issues:}
+			\vspace{.5em}
+			\begin{itemize}
+				\item<4-> The leader is a \textbf{bottleneck} for all requests\\
+					\vspace{.5em}
+				\item<5-> \textbf{Sensitive to higher latency} between nodes
+					\vspace{.5em}
+				\item<6-> \textbf{Takes time to reconverge} when disrupted (e.g. node going down)
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{The data model of object storage}
+	Object storage is basically a \textbf{key-value store}:
+	\vspace{.5em}
+
+	{\scriptsize
+		\begin{center}
+		\begin{tabular}{|l|p{7cm}|}
+			\hline
+			\textbf{Key: file path + name} & \textbf{Value: file data + metadata} \\
+			\hline
+			\hline
+			\texttt{index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 24929} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{img/logo.svg} &
+				\texttt{Content-Type: text/svg+xml} \newline
+				\texttt{Content-Length: 13429} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{download/index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 26563} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+		\end{tabular}
+		\end{center}
+		}
+
+	\vspace{1em}
+	\begin{itemize}
+		\item<2> Maps well to CRDT data types
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Performance gains in practice}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/perf/endpoint_latency_0.7_0.8_minio.png}
+	\end{center}
+\end{frame}
+
+
+% ======================================== TIMELINE
+% ======================================== TIMELINE
+% ======================================== TIMELINE
+
+\section{Recent developments}
+
+% ====================== v0.7.0 ===============================
+
+\begin{frame}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{April 2022 - Garage v0.7.0}
+	Focus on \underline{observability and ecosystem integration}
+	\vspace{2em}
+	\begin{itemize}
+		\item \textbf{Monitoring:} metrics and traces, using OpenTelemetry
+			\vspace{1em}
+		\item Replication modes with 1 or 2 copies / weaker consistency
+			\vspace{1em}
+		\item Kubernetes integration for node discovery
+			\vspace{1em}
+		\item Admin API (v0.7.2)
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Metrics (Prometheus + Grafana)}
+	\begin{center}
+		\includegraphics[width=.9\linewidth]{../assets/screenshots/grafana_dashboard.png}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Traces (Jaeger)}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/screenshots/jaeger_listobjects.png}
+	\end{center}
+\end{frame}
+
+% ====================== v0.8.0 ===============================
+
+\begin{frame}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{November 2022 - Garage v0.8.0}
+	Focus on \underline{performance}
+	\vspace{2em}
+	\begin{itemize}
+		\item \textbf{Alternative metadata DB engines} (LMDB, Sqlite)
+			\vspace{1em}
+		\item \textbf{Performance improvements:} block streaming, various optimizations...
+			\vspace{1em}
+		\item Bucket quotas (max size, max \#objects)
+			\vspace{1em}
+		\item Quality of life improvements, observability, etc.
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{About metadata DB engines}
+	\textbf{Issues with Sled:}
+	\vspace{1em}
+	\begin{itemize}
+		\item Huge files on disk
+			\vspace{.5em}
+		\item Unpredictable performance, especially on HDD
+			\vspace{.5em}
+		\item API limitations
+			\vspace{.5em}
+		\item Not actively maintained
+	\end{itemize}
+
+	\vspace{2em}
+	\textbf{LMDB:} very stable, good performance, file size is reasonable\\
+	\textbf{Sqlite} also available as a second choice
+
+	\vspace{1em}
+	Sled will be removed in Garage v1.0
+\end{frame}
+
+\begin{frame}
+	\frametitle{DB engine performance comparison}
+	\begin{center}
+		\includegraphics[width=.6\linewidth]{../assets/perf/db_engine.png}
+	\end{center}
+	NB: Sqlite was slow due to synchronous mode, now configurable
+\end{frame}
+
+\begin{frame}
+	\frametitle{Block streaming}
+	\begin{center}
+		\only<1>{\includegraphics[width=.8\linewidth]{../assets/schema-streaming-1.png}}
+		\only<2>{\includegraphics[width=.8\linewidth]{../assets/schema-streaming-2.png}}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{TTFB benchmark}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/perf/ttfb.png}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Throughput benchmark}
+	\begin{center}
+		\includegraphics[width=.7\linewidth]{../assets/perf/io-0.7-0.8-minio.png}
+	\end{center}
+\end{frame}
+
+% ====================== v0.9.0 ===============================
+
+\begin{frame}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{October 2023 - Garage v0.9.0}
+	Focus on \underline{streamlining \& usability}
+	\vspace{2em}
+	\begin{itemize}
+		\item Support multiple HDDs per node
+			\vspace{1em}
+		\item S3 compatibility: 
+			\vspace{1em}
+			\begin{itemize}
+				\item support basic lifecycle configurations
+					\vspace{.5em}
+				\item allow for multipart upload part retries
+			\end{itemize}
+			\vspace{1em}
+		\item LMDB by default, deprecation of Sled
+			\vspace{1em}
+		\item New layout computation algorithm
+	\end{itemize}
+\end{frame}
+
+
+\begin{frame}
+	\frametitle{Layout computation}
+	\begin{overprint}
+		\onslide<1>
+		\begin{center}
+			\includegraphics[width=\linewidth, trim=0 0 0 -4cm]{../assets/screenshots/garage_status_0.9_prod_zonehl.png}
+		\end{center}
+		\onslide<2>
+		\begin{center}
+			\includegraphics[width=.7\linewidth]{../assets/map.png}
+		\end{center}
+	\end{overprint}
+	\vspace{1em}
+	Garage stores replicas on different zones when possible
+\end{frame}
+
+\begin{frame}
+	\frametitle{What a "layout" is}
+		\textbf{A layout is a precomputed index table:}
+		\vspace{1em}
+
+		{\footnotesize
+			\begin{center}
+			\begin{tabular}{|l|l|l|l|}
+				\hline
+				\textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\
+				\hline
+				\hline
+				Partition 0 & df-ymk (bespin) & Abricot (scorpio) & Courgette (neptune) \\
+				\hline
+				Partition 1 & Ananas (scorpio) & Courgette (neptune) & df-ykl (bespin) \\
+				\hline
+				Partition 2 & df-ymf (bespin) & Celeri (neptune) & Abricot (scorpio) \\
+				\hline
+				\hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ \\
+				\hline
+				Partition 255 & Concombre (neptune) & df-ykl (bespin) & Abricot (scorpio) \\
+				\hline
+			\end{tabular}
+			\end{center}
+		}
+
+	\vspace{2em}
+	\visible<2->{
+		The index table is built centrally using an optimal algorithm,\\
+		then propagated to all nodes
+	}
+
+	\vspace{1em}
+	\visible<3->{
+		\footnotesize
+		Oulamara, M., \& Auvolat, A. (2023). \emph{An algorithm for geo-distributed and redundant storage in Garage}.\\ arXiv preprint arXiv:2302.13798.
+	}
+\end{frame}
+
+
+
+% ====================== v0.10.0 ===============================
+
+\begin{frame}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{October 2023 - Garage v0.10.0 beta}
+	Focus on \underline{consistency}
+	\vspace{2em}
+	\begin{itemize}
+		\item Fix consistency issues when reshuffling data
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Working with weak consistency}
+	Not using consensus limits us to the following:
+	\vspace{2em}
+	\begin{itemize}
+		\item<2-> \textbf{Conflict-free replicated data types} (CRDT)\\
+			\vspace{1em}
+			{\footnotesize Non-transactional key-value stores such as S3 are equivalent to a simple CRDT:\\
+			a map of \textbf{last-writer-wins registers} (each key is its own CRDT)}
+			\vspace{1.5em}
+		\item<3-> \textbf{Read-after-write consistency}\\
+			\vspace{1em}
+			{\footnotesize Can be implemented using quorums on read and write operations}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}[t]
+	\frametitle{CRDT read-after-write consistency using quorums}
+
+	\vspace{1em}
+	{\small
+		\textbf{Property:} If client 1 did an operation $write(x)$ and received an OK response,\\
+			\hspace{2cm} and client 2 starts an operation $read()$ after client 1 received OK,\\
+			\hspace{2cm} then client 2 will read a value $x' \sqsupseteq x$.
+	}
+
+	\vspace{1.5em}
+	\begin{overprint}
+		\onslide<2-9>
+		\begin{figure}
+			\centering
+			\footnotesize
+			\def\svgwidth{.7\textwidth}
+			\only<2>{\import{../assets/lattice/}{lattice1.pdf_tex}}%
+			\only<3>{\import{../assets/lattice/}{lattice2.pdf_tex}}%
+			\only<4>{\import{../assets/lattice/}{lattice3.pdf_tex}}%
+			\only<5>{\import{../assets/lattice/}{lattice4.pdf_tex}}%
+			\only<6>{\import{../assets/lattice/}{lattice5.pdf_tex}}%
+			\only<7>{\import{../assets/lattice/}{lattice6.pdf_tex}}%
+			\only<8>{\import{../assets/lattice/}{lattice7.pdf_tex}}%
+			\only<9>{\import{../assets/lattice/}{lattice8.pdf_tex}}%
+		\end{figure}
+		
+		\onslide<10>
+		\begin{minipage}{.10\textwidth}
+			~
+		\end{minipage}
+		\begin{minipage}{.40\textwidth}
+			\footnotesize
+			\textbf{Algorithm $write(x)$:}
+			\begin{enumerate}
+				\item Broadcast $write(x)$ to all nodes
+				\item Wait for $k > n/2$ nodes to reply OK
+				\item Return OK
+			\end{enumerate}
+		\end{minipage}
+		\begin{minipage}{.40\textwidth}
+			\footnotesize
+			\vspace{1em}
+			\textbf{Algorithm $read()$:}
+			\begin{enumerate}
+				\item Broadcast $read()$ to all nodes
+				\item Wait for $k > n/2$ nodes to reply\\
+					with values $x_1, \dots, x_k$
+				\item Return $x_1 \sqcup \dots \sqcup x_k$
+			\end{enumerate}
+		\end{minipage}
+	\end{overprint}
+\end{frame}
+
+\begin{frame}
+	\frametitle{A hard problem: layout changes}
+	\begin{itemize}
+		\item We rely on quorums $k > n/2$ within each partition:\\
+			$$n=3,~~~~~~~k\ge 2$$
+		\item<2-> When rebalancing, the set of nodes responsible for a partition can change:\\
+
+			\vspace{1em}
+			\begin{minipage}{.04\linewidth}~
+			\end{minipage}
+			\begin{minipage}{.40\linewidth}
+			{\tiny
+				\begin{tabular}{|l|l|l|l|}
+					\hline
+					\textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\
+					\hline
+					\hline
+					Partition 0 & \textcolor{Crimson}{df-ymk}  & Abricot  & \textcolor{Crimson}{Courgette} \\
+					\hline
+					Partition 1 & Ananas  & \textcolor{Crimson}{Courgette} & \textcolor{Crimson}{df-ykl}  \\
+					\hline
+					Partition 2 & \textcolor{Crimson}{df-ymf}  & \textcolor{Crimson}{Celeri} & Abricot  \\
+					\hline
+					\hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ \\
+					\hline
+				\end{tabular}
+			}
+			\end{minipage}
+			\begin{minipage}{.04\linewidth}
+				$\to$
+			\end{minipage}
+			\begin{minipage}{.40\linewidth}
+			{\tiny
+				\begin{tabular}{|l|l|l|l|}
+					\hline
+					\textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\
+					\hline
+					\hline
+					Partition 0 & \textcolor{ForestGreen}{Dahlia}  & Abricot  & \textcolor{ForestGreen}{Eucalyptus} \\
+					\hline
+					Partition 1 & Ananas  & \textcolor{ForestGreen}{Euphorbe}  & \textcolor{ForestGreen}{Doradille} \\
+					\hline
+					Partition 2 & \textcolor{ForestGreen}{Dahlia}  & \textcolor{ForestGreen}{Echinops} & Abricot  \\
+					\hline
+					\hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ \\
+					\hline
+				\end{tabular}
+			}
+			\end{minipage}
+
+			\vspace{2em}
+		\item<3-> During the rebalancing, new nodes don't yet have the data,\\
+			~~~~~~~~~~~~~~~~~~~and old nodes want to get rid of the data to free up space\\
+			\vspace{1.2em}
+			$\to$ risk of inconsistency, \textbf{how to coordinate?}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Handling layout changes without losing consistency}
+	\begin{minipage}{.55\textwidth}
+		\begin{itemize}
+			\item \textbf{Solution:}\\
+				\vspace{.5em}
+				\begin{itemize}
+					\item keep track of data transfer to new nodes
+						\vspace{.5em}
+					\item use multiple write quorums\\
+						(new nodes + old nodes\\
+						while data transfer is in progress)
+						\vspace{.5em}
+					\item switching reads to new nodes\\
+						only once copy is finished
+				\end{itemize}
+				\vspace{1em}
+			\item \textbf{Implemented} in v0.10
+				\vspace{1em}
+			\item \textbf{Validated} with Jepsen testing
+		\end{itemize}
+	\end{minipage}
+	\begin{minipage}{.23\textwidth}
+		\includegraphics[width=3cm]{../assets/jepsen-0.9.png}\\
+		{\footnotesize Garage v0.9.0}
+	\end{minipage}
+	\begin{minipage}{.2\textwidth}
+		\includegraphics[width=3cm]{../assets/jepsen-0.10.png}\\
+		{\footnotesize Garage v0.10 beta}
+	\end{minipage}
+\end{frame}
+
+% ====================== v0.10.0 ===============================
+
+\begin{frame}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Towards v1.0...}
+	Focus on \underline{security \& stability}
+	\vspace{2em}
+	\begin{itemize}
+		\item \textbf{Security audit} in progress by Radically Open Security
+			\vspace{1em}
+		\item Misc. S3 features (SSE-C, ...) and compatibility fixes
+			\vspace{1em}
+		\item Improve UX
+			\vspace{1em}
+		\item Fix bugs
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{...and beyond!}
+	\begin{center}
+		\includegraphics[width=.6\linewidth]{../assets/survey_requested_features.png}
+	\end{center}
+\end{frame}
+
+% ======================================== OPERATING
+% ======================================== OPERATING
+% ======================================== OPERATING
+
+
+\section{Operating big Garage clusters}
+
+\begin{frame}
+	\frametitle{Operating Garage}
+	\begin{center}
+		\only<1-2>{
+			\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_0.10.png}
+			\\\vspace{1em}
+			\visible<2>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_unhealthy_0.10.png}}
+		}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Garage's architecture}
+	\begin{center}
+		\only<1>{\includegraphics[width=.45\linewidth]{../assets/garage.drawio.pdf}}%
+		\only<2>{\includegraphics[width=.6\linewidth]{../assets/garage_sync.drawio.pdf}}%
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Digging deeper}
+	\begin{center}
+		\only<1>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_stats_0.10.png}}
+		\only<2>{\includegraphics[width=.5\linewidth]{../assets/screenshots/garage_worker_list_0.10.png}}
+		\only<3>{\includegraphics[width=.6\linewidth]{../assets/screenshots/garage_worker_param_0.10.png}}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Potential limitations and bottlenecks}
+	\begin{itemize}
+		\item Global:
+			\begin{itemize}
+				\item Max. $\sim$100 nodes per cluster (excluding gateways)
+			\end{itemize}
+			\vspace{1em}
+		\item Metadata:
+			\begin{itemize}
+				\item One big bucket = bottleneck, object list on 3 nodes only
+			\end{itemize}
+			\vspace{1em}
+		\item Block manager:
+			\begin{itemize}
+				\item Lots of small files on disk
+				\item Processing the resync queue can be slow
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Deployment advice for very large clusters}
+	\begin{itemize}
+		\item Metadata storage:
+			\begin{itemize}
+				\item ZFS mirror (x2) on fast NVMe
+				\item Use LMDB storage engine
+			\end{itemize}
+			\vspace{.5em}
+		\item Data block storage:
+			\begin{itemize}
+				\item Use Garage's native multi-HDD support
+				\item XFS on individual drives
+				\item Increase block size (1MB $\to$ 10MB, requires more RAM and good networking)
+				\item Tune \texttt{resync-tranquility} and \texttt{resync-worker-count} dynamically
+			\end{itemize}
+			\vspace{.5em}
+		\item Other :
+			\begin{itemize}
+				\item Split data over several buckets
+				\item Use less than 100 storage nodes
+				\item Use gateway nodes
+			\end{itemize}
+			\vspace{.5em}
+	\end{itemize}
+	Our deployments: $< 10$ TB. Some people have done more!
+\end{frame}
+
+
+% ======================================== END
+% ======================================== END
+% ======================================== END
+
+\begin{frame}
+	\frametitle{Where to find us}
+	\begin{center}
+			\includegraphics[width=.25\linewidth]{../../logo/garage_hires.png}\\
+			\vspace{-1em}
+		\url{https://garagehq.deuxfleurs.fr/}\\
+		\url{mailto:garagehq@deuxfleurs.fr}\\
+		\texttt{\#garage:deuxfleurs.fr} on Matrix
+
+		\vspace{1.5em}
+			\includegraphics[width=.06\linewidth]{../assets/logos/rust_logo.png}
+			\includegraphics[width=.13\linewidth]{../assets/logos/AGPLv3_Logo.png}
+	\end{center}
+\end{frame}
+
+\end{document}
+
+%% vim: set ts=4 sw=4 tw=0 noet spelllang=en :

doc/talks/2024-02-29-capitoul/.gitignore

@@ -0,0 +1,17 @@
+*
+
+!*.txt
+!*.md
+
+!assets
+
+!.gitignore
+!*.svg
+!*.png
+!*.jpg
+!*.tex
+!Makefile
+!.gitignore
+!assets/*.drawio.pdf
+
+!talk.pdf

doc/talks/2024-02-29-capitoul/Makefile

@@ -0,0 +1,10 @@
+ASSETS=../assets/logos/deuxfleurs.pdf
+
+talk.pdf: talk.tex $(ASSETS)
+	pdflatex talk.tex
+
+%.pdf: %.svg
+	inkscape -D -z --file=$^ --export-pdf=$@
+
+%.pdf_tex: %.svg
+	inkscape -D -z --file=$^ --export-pdf=$@ --export-latex

doc/talks/2024-02-29-capitoul/talk.tex

@@ -0,0 +1,543 @@
+\nonstopmode
+\documentclass[aspectratio=169,xcolor={svgnames}]{beamer}
+\usepackage[utf8]{inputenc}
+% \usepackage[frenchb]{babel}
+\usepackage{amsmath}
+\usepackage{mathtools}
+\usepackage{breqn}
+\usepackage{multirow}
+\usetheme{boxes}
+\usepackage{graphicx}
+\usepackage{import}
+\usepackage{adjustbox}
+\usepackage[absolute,overlay]{textpos}
+%\useoutertheme[footline=authortitle,subsection=false]{miniframes}
+%\useoutertheme[footline=authorinstitute,subsection=false]{miniframes}
+\useoutertheme{infolines}
+\setbeamertemplate{headline}{}
+
+\beamertemplatenavigationsymbolsempty
+
+\definecolor{TitleOrange}{RGB}{255,137,0}
+\setbeamercolor{title}{fg=TitleOrange}
+\setbeamercolor{frametitle}{fg=TitleOrange}
+
+\definecolor{ListOrange}{RGB}{255,145,5}
+\setbeamertemplate{itemize item}{\color{ListOrange}$\blacktriangleright$}
+
+\definecolor{verygrey}{RGB}{70,70,70}
+\setbeamercolor{normal text}{fg=verygrey}
+
+
+\usepackage{tabu}
+\usepackage{multicol}
+\usepackage{vwcol}
+\usepackage{stmaryrd}
+\usepackage{graphicx}
+
+\usepackage[normalem]{ulem}
+
+\AtBeginSection[]{
+  \begin{frame}
+  \vfill
+  \centering
+  \begin{beamercolorbox}[sep=8pt,center,shadow=true,rounded=true]{title}
+    \usebeamerfont{title}\insertsectionhead\par%
+  \end{beamercolorbox}
+  \vfill
+  \end{frame}
+}
+
+\title{Garage}
+\author{Alex Auvolat, Deuxfleurs}
+\date{Capitoul, 2024-02-29}
+
+\begin{document}
+
+\begin{frame}
+	\centering
+	\includegraphics[width=.3\linewidth]{../../sticker/Garage.png}
+	\vspace{1em}
+
+	{\large\bf Alex Auvolat, Deuxfleurs Association}
+	\vspace{1em}
+
+	\url{https://garagehq.deuxfleurs.fr/}
+
+	Matrix channel: \texttt{\#garage:deuxfleurs.fr}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Who I am}
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.4\linewidth, valign=t]{../assets/alex.jpg}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Alex Auvolat}\\
+			PhD; co-founder of Deuxfleurs
+		\end{column}
+		\begin{column}{.2\textwidth}
+			~
+		\end{column}
+	\end{columns}
+	\vspace{2em}
+
+	\begin{columns}[t]
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.5\linewidth, valign=t]{../assets/logos/deuxfleurs.pdf}
+		\end{column}
+		\begin{column}{.6\textwidth}
+			\textbf{Deuxfleurs}\\
+			A non-profit self-hosting collective,\\
+			member of the CHATONS network
+		\end{column}
+		\begin{column}{.2\textwidth}
+			\centering
+			\adjincludegraphics[width=.7\linewidth, valign=t]{../assets/logos/logo_chatons.png}
+		\end{column}
+	\end{columns}
+
+\end{frame}
+
+\begin{frame}
+	\frametitle{Our objective at Deuxfleurs}
+	
+	\begin{center}
+		\textbf{Promote self-hosting and small-scale hosting\\
+			as an alternative to large cloud providers}
+	\end{center}
+	\vspace{2em}
+	\visible<2->{
+		Why is it hard?
+		\vspace{2em}
+		\begin{center}
+			\textbf{\underline{Resilience}}\\
+			{\footnotesize we want good uptime/availability with low supervision}
+		\end{center}
+	}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Our very low-tech infrastructure}
+
+	\only<1,3-6>{
+		\begin{itemize}
+			\item \textcolor<4->{gray}{Commodity hardware (e.g. old desktop PCs)\\
+				\vspace{.5em}
+				\visible<3->{{\footnotesize (can die at any time)}}}
+				\vspace{1.5em}
+			\item<4-> \textcolor<6->{gray}{Regular Internet (e.g. FTTB, FTTH) and power grid connections\\
+				\vspace{.5em}
+				\visible<5->{{\footnotesize (can be unavailable randomly)}}}
+				\vspace{1.5em}
+			\item<6-> \textbf{Geographical redundancy} (multi-site replication)
+		\end{itemize}
+	}
+	\only<2>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/neptune.jpg}
+		\end{center}
+	}
+	\only<7>{
+		\begin{center}
+			\includegraphics[width=.8\linewidth]{../assets/inframap_jdll2023.pdf}
+		\end{center}
+	}
+\end{frame}
+
+\begin{frame}
+	\frametitle{How to make this happen}
+	\begin{center}
+		\only<1>{\includegraphics[width=.8\linewidth]{../assets/intro/slide1.png}}%
+		\only<2>{\includegraphics[width=.8\linewidth]{../assets/intro/slide2.png}}%
+		\only<3>{\includegraphics[width=.8\linewidth]{../assets/intro/slide3.png}}%
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Distributed file systems are slow}
+	File systems are complex, for example:
+	\vspace{1em}
+	\begin{itemize}
+		\item Concurrent modification by several processes
+			\vspace{1em}
+		\item Folder hierarchies
+			\vspace{1em}
+		\item Other requirements of the POSIX spec (e.g.~locks)
+	\end{itemize}
+	\vspace{1em}
+	Coordination in a distributed system is costly
+
+	\vspace{1em}
+	Costs explode with commodity hardware / Internet connections\\
+	{\small (we experienced this!)}
+\end{frame}
+
+\begin{frame}
+	\frametitle{A simpler solution: object storage}
+	Only two operations:
+	\vspace{1em}
+	\begin{itemize}
+		\item Put an object at a key
+			\vspace{1em}
+		\item Retrieve an object from its key
+	\end{itemize}
+	\vspace{1em}
+	{\footnotesize (and a few others)}
+
+	\vspace{1em}
+	Sufficient for many applications!
+\end{frame}
+
+\begin{frame}
+	\frametitle{A simpler solution: object storage}
+		\begin{center}
+			\includegraphics[height=6em]{../assets/logos/Amazon-S3.jpg}
+			\hspace{3em}
+			\visible<2->{\includegraphics[height=5em]{../assets/logos/minio.png}}
+			\hspace{3em}
+			\visible<3>{\includegraphics[height=6em]{../../logo/garage_hires_crop.png}}
+		\end{center}
+		\vspace{1em}
+	S3: a de-facto standard, many compatible applications
+
+	\vspace{1em}
+	\visible<2->{MinIO is self-hostable but not suited for geo-distributed deployments}
+
+	\vspace{1em}
+	\visible<3->{\textbf{Garage is a self-hosted drop-in replacement for the Amazon S3 object store}}
+\end{frame}
+
+% --------- BASED ON CRDTS ----------
+
+\section{Principle 1: based on CRDTs}
+
+\begin{frame}
+	\frametitle{CRDTs / weak consistency instead of consensus}
+
+	\underline{Internally, Garage uses only CRDTs} (conflict-free replicated data types)
+
+	\vspace{2em}
+	Why not Raft, Paxos, ...? Issues of consensus algorithms:
+
+	\vspace{1em}
+	\begin{itemize}
+		\item<2-> \textbf{Software complexity}
+			\vspace{1em}
+		\item<3-> \textbf{Performance issues:}
+			\vspace{.5em}
+			\begin{itemize}
+				\item<4-> The leader is a \textbf{bottleneck} for all requests\\
+					\vspace{.5em}
+				\item<5-> \textbf{Sensitive to higher latency} between nodes
+					\vspace{.5em}
+				\item<6-> \textbf{Takes time to reconverge} when disrupted (e.g. node going down)
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{The data model of object storage}
+	Object storage is basically a \textbf{key-value store}:
+	\vspace{.5em}
+
+	{\scriptsize
+		\begin{center}
+		\begin{tabular}{|l|p{7cm}|}
+			\hline
+			\textbf{Key: file path + name} & \textbf{Value: file data + metadata} \\
+			\hline
+			\hline
+			\texttt{index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 24929} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{img/logo.svg} &
+				\texttt{Content-Type: text/svg+xml} \newline
+				\texttt{Content-Length: 13429} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+			\texttt{download/index.html} &
+				\texttt{Content-Type: text/html; charset=utf-8} \newline
+				\texttt{Content-Length: 26563} \newline
+				\texttt{<binary blob>} \\ 
+			\hline
+		\end{tabular}
+		\end{center}
+		}
+
+	\vspace{.5em}
+	\begin{itemize}
+		\item<2-> Maps well to CRDT data types
+		\item<3> Read-after-write consistency with quorums
+	\end{itemize}
+\end{frame}
+
+
+\begin{frame}
+	\frametitle{Performance gains in practice}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/perf/endpoint_latency_0.7_0.8_minio.png}
+	\end{center}
+\end{frame}
+
+% --------- GEO-DISTRIBUTED MODEL ----------
+
+\section{Principle 2: geo-distributed data model}
+
+\begin{frame}
+	\frametitle{Key-value stores, upgraded: the Dynamo model}
+	\textbf{Two keys:}
+	\begin{itemize}
+		\item Partition key: used to divide data into partitions {\small (a.k.a.~shards)}
+		\item Sort key: used to identify items inside a partition
+	\end{itemize}
+
+	\vspace{1em}
+
+	\begin{center}
+	\begin{tabular}{|l|l|p{3cm}|}
+		\hline
+		\textbf{Partition key: bucket} & \textbf{Sort key: filename} & \textbf{Value} \\
+		\hline
+		\hline
+		\texttt{website} & \texttt{index.html} & (file data) \\
+		\hline
+		\texttt{website} & \texttt{img/logo.svg} & (file data) \\
+		\hline
+		\texttt{website} & \texttt{download/index.html} & (file data) \\
+		\hline
+		\hline
+		\texttt{backup} & \texttt{borg/index.2822} & (file data) \\
+		\hline
+		\texttt{backup} & \texttt{borg/data/2/2329} & (file data) \\
+		\hline
+		\texttt{backup} & \texttt{borg/data/2/2680} & (file data) \\
+		\hline
+		\hline
+		\texttt{private} & \texttt{qq3a2nbe1qjq0ebbvo6ocsp6co} & (file data) \\
+		\hline
+	\end{tabular}
+	\end{center}
+\end{frame}
+
+
+\begin{frame}
+	\frametitle{Layout computation}
+	\begin{overprint}
+		\onslide<1>
+		\begin{center}
+			\includegraphics[width=\linewidth, trim=0 0 0 -4cm]{../assets/screenshots/garage_status_0.9_prod_zonehl.png}
+		\end{center}
+		\onslide<2>
+		\begin{center}
+			\includegraphics[width=.7\linewidth]{../assets/map.png}
+		\end{center}
+	\end{overprint}
+	\vspace{1em}
+	Garage stores replicas on different zones when possible
+\end{frame}
+
+\begin{frame}
+	\frametitle{What a "layout" is}
+		\textbf{A layout is a precomputed index table:}
+		\vspace{1em}
+
+		{\footnotesize
+			\begin{center}
+			\begin{tabular}{|l|l|l|l|}
+				\hline
+				\textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\
+				\hline
+				\hline
+				Partition 0 & df-ymk (bespin) & Abricot (scorpio) & Courgette (neptune) \\
+				\hline
+				Partition 1 & Ananas (scorpio) & Courgette (neptune) & df-ykl (bespin) \\
+				\hline
+				Partition 2 & df-ymf (bespin) & Celeri (neptune) & Abricot (scorpio) \\
+				\hline
+				\hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ \\
+				\hline
+				Partition 255 & Concombre (neptune) & df-ykl (bespin) & Abricot (scorpio) \\
+				\hline
+			\end{tabular}
+			\end{center}
+		}
+
+	\vspace{2em}
+	\visible<2->{
+		The index table is built centrally using an optimal algorithm,\\
+		then propagated to all nodes
+	}
+
+	\vspace{1em}
+	\visible<3->{
+		\footnotesize
+		Oulamara, M., \& Auvolat, A. (2023). \emph{An algorithm for geo-distributed and redundant storage in Garage}.\\ arXiv preprint arXiv:2302.13798.
+	}
+\end{frame}
+
+
+\begin{frame}
+	\frametitle{The relationship between \emph{partition} and \emph{partition key}}
+	\begin{center}
+	\begin{tabular}{|l|l|l|l|}
+		\hline
+		\textbf{Partition key} & \textbf{Partition} & \textbf{Sort key} & \textbf{Value} \\
+		\hline
+		\hline
+		\texttt{website} & Partition 12 & \texttt{index.html} & (file data) \\
+		\hline
+		\texttt{website} & Partition 12 & \texttt{img/logo.svg} & (file data) \\
+		\hline
+		\texttt{website} & Partition 12 &\texttt{download/index.html} & (file data) \\
+		\hline
+		\hline
+		\texttt{backup} & Partition 42 & \texttt{borg/index.2822} & (file data) \\
+		\hline
+		\texttt{backup} & Partition 42 & \texttt{borg/data/2/2329} & (file data) \\
+		\hline
+		\texttt{backup} & Partition 42 & \texttt{borg/data/2/2680} & (file data) \\
+		\hline
+		\hline
+		\texttt{private} & Partition 42 & \texttt{qq3a2nbe1qjq0ebbvo6ocsp6co} & (file data) \\
+		\hline
+	\end{tabular}
+	\end{center}
+	\vspace{1em}
+	\textbf{To read or write an item:} hash partition key
+	\\ \hspace{5cm} $\to$ determine partition number (first 8 bits)
+	\\ \hspace{5cm} $\to$ find associated nodes
+\end{frame}
+
+\begin{frame}
+	\frametitle{Garage's internal data structures}
+	\centering
+	\includegraphics[width=.75\columnwidth]{../assets/garage_tables.pdf}
+\end{frame}
+
+% ---------- OPERATING GARAGE ---------
+
+\section{Operating Garage clusters}
+
+\begin{frame}
+	\frametitle{Operating Garage}
+	\begin{center}
+		\only<1-2>{
+			\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_0.10.png}
+			\\\vspace{1em}
+			\visible<2>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_unhealthy_0.10.png}}
+		}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Background synchronization}
+	\begin{center}
+		\includegraphics[width=.6\linewidth]{../assets/garage_sync.drawio.pdf}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Digging deeper}
+	\begin{center}
+		\only<1>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_stats_0.10.png}}
+		\only<2>{\includegraphics[width=.5\linewidth]{../assets/screenshots/garage_worker_list_0.10.png}}
+		\only<3>{\includegraphics[width=.6\linewidth]{../assets/screenshots/garage_worker_param_0.10.png}}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Monitoring with Prometheus + Grafana}
+	\begin{center}
+		\includegraphics[width=.9\linewidth]{../assets/screenshots/grafana_dashboard.png}
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Debugging with traces}
+	\begin{center}
+		\includegraphics[width=.8\linewidth]{../assets/screenshots/jaeger_listobjects.png}
+	\end{center}
+\end{frame}
+
+% ---------- SCALING GARAGE ---------
+
+\section{Scaling Garage clusters}
+
+\begin{frame}
+	\frametitle{Potential limitations and bottlenecks}
+	\begin{itemize}
+		\item Global:
+			\begin{itemize}
+				\item Max. $\sim$100 nodes per cluster (excluding gateways)
+			\end{itemize}
+			\vspace{1em}
+		\item Metadata:
+			\begin{itemize}
+				\item One big bucket = bottleneck, object list on 3 nodes only
+			\end{itemize}
+			\vspace{1em}
+		\item Block manager:
+			\begin{itemize}
+				\item Lots of small files on disk
+				\item Processing the resync queue can be slow
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Deployment advice for very large clusters}
+	\begin{itemize}
+		\item Metadata storage:
+			\begin{itemize}
+				\item ZFS mirror (x2) on fast NVMe
+				\item Use LMDB storage engine
+			\end{itemize}
+			\vspace{.5em}
+		\item Data block storage:
+			\begin{itemize}
+				\item Use Garage's native multi-HDD support
+				\item XFS on individual drives
+				\item Increase block size (1MB $\to$ 10MB, requires more RAM and good networking)
+				\item Tune \texttt{resync-tranquility} and \texttt{resync-worker-count} dynamically
+			\end{itemize}
+			\vspace{.5em}
+		\item Other :
+			\begin{itemize}
+				\item Split data over several buckets
+				\item Use less than 100 storage nodes
+				\item Use gateway nodes
+			\end{itemize}
+			\vspace{.5em}
+	\end{itemize}
+	Our deployments: $< 10$ TB. Some people have done more!
+\end{frame}
+
+
+% ======================================== END
+% ======================================== END
+% ======================================== END
+
+\begin{frame}
+	\frametitle{Where to find us}
+	\begin{center}
+			\includegraphics[width=.25\linewidth]{../../logo/garage_hires.png}\\
+			\vspace{-1em}
+		\url{https://garagehq.deuxfleurs.fr/}\\
+		\url{mailto:garagehq@deuxfleurs.fr}\\
+		\texttt{\#garage:deuxfleurs.fr} on Matrix
+
+		\vspace{1.5em}
+			\includegraphics[width=.06\linewidth]{../assets/logos/rust_logo.png}
+			\includegraphics[width=.13\linewidth]{../assets/logos/AGPLv3_Logo.png}
+	\end{center}
+\end{frame}
+
+\end{document}
+
+%% vim: set ts=4 sw=4 tw=0 noet spelllang=en :

doc/talks/assets/.gitignore

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+deuxfleurs.pdf
+timeline-22-24.pdf
+lattice*.pdf_tex
+lattice*.pdf
+
+# tmp files generated by krita
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+    <text
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+         id="tspan4278"
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+         id="tspan4278"
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+         id="tspan3705"
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+         x="6.9525447"
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+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan3705-5"
+         style="fill:#000000;stroke-width:0.264583"
+         x="6.9525447"
+         y="65.261436">$read()$:</tspan></text>
+    <text
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+         id="tspan3748"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="24.042637">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan3748-2"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="33.02087">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
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+         id="tspan3748-6"
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+       id="path3663-6-6-4"
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+       cy="70.942116"
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+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         sodipodi:role="line"
+         id="tspan3748-65"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="73.643356">$\to \{\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan4278"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
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+  </g>
+</svg>

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+      <text
+         xml:space="preserve"
+         style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;text-align:center;text-anchor:middle;stroke-width:0.264583;fill:#000000"
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+           id="tspan1115-5"
+           style="stroke-width:0.264583;fill:#000000"
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+           y="40.841526">$\{a,b\}$</tspan></text>
+      <text
+         xml:space="preserve"
+         style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;text-align:center;text-anchor:middle;stroke-width:0.264583;fill:#000000"
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+    <path
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+       id="path1300-2-2-6-9"
+       sodipodi:nodetypes="cc" />
+    <circle
+       style="fill:#ff0000;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
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+       cy="95.24971"
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+    <circle
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+       id="path3663-3"
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+       cy="67.645035"
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+    <circle
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+    <circle
+       style="fill:#008000;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
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+       cx="18.004833"
+       cy="30.371933"
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+    <circle
+       style="fill:#800080;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-6-6"
+       cx="18.004833"
+       cy="21.341394"
+       r="2.7302806" />
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;stroke-width:0.264583;fill:#000000"
+       x="6.9525447"
+       y="13.702217"
+       id="text3707"><tspan
+         sodipodi:role="line"
+         id="tspan3705"
+         style="stroke-width:0.264583;fill:#000000"
+         x="6.9525447"
+         y="13.702217">$write(\{a\})$:</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="6.9525447"
+       y="65.261436"
+       id="text3707-1"><tspan
+         sodipodi:role="line"
+         id="tspan3705-5"
+         style="fill:#000000;stroke-width:0.264583"
+         x="6.9525447"
+         y="65.261436">$read()$:</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="23.457415"
+       y="24.042637"
+       id="text3750"><tspan
+         sodipodi:role="line"
+         id="tspan3748"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="24.042637">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="23.457415"
+       y="33.02087"
+       id="text3750-3"><tspan
+         sodipodi:role="line"
+         id="tspan3748-2"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="33.02087">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#999999;stroke-width:0.264583"
+       x="23.457415"
+       y="41.972523"
+       id="text3750-0"><tspan
+         sodipodi:role="line"
+         id="tspan3748-6"
+         style="fill:#999999;stroke-width:0.264583"
+         x="23.457415"
+         y="41.972523">$\not\sqsupseteq \{a\}$</tspan></text>
+    <circle
+       style="fill:#ff0000;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-6-6-4"
+       cx="18.004833"
+       cy="70.942116"
+       r="2.7302806" />
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="23.457415"
+       y="73.643356"
+       id="text3750-7"><tspan
+         sodipodi:role="line"
+         id="tspan3748-65"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="73.643356">$\to \{\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="14.395845"
+       y="52.022549"
+       id="text4280"><tspan
+         sodipodi:role="line"
+         id="tspan4278"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="52.022549">return OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="14.395845"
+       y="92.005798"
+       id="text4280-3"><tspan
+         sodipodi:role="line"
+         id="tspan4278-7"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="92.005798">return $\{\}\sqcup\{a\}=\{a\}$</tspan></text>
+    <circle
+       style="fill:#800080;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-1-5"
+       cx="18.004833"
+       cy="81.007744"
+       r="2.7302806" />
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="23.457415"
+       y="83.577797"
+       id="text3750-0-6"><tspan
+         sodipodi:role="line"
+         id="tspan3748-6-9"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="83.577797">$\to \{a\}$</tspan></text>
+  </g>
+</svg>

doc/talks/assets/lattice/lattice8.svg

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+         id="tspan3748"
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