Performance improvements included in this PR:
- [x] Use `Bytes` at a few places where appropriate, instead of `Vec<u8>`, to reduce the number of copies
- [x] StreamChunker now accumulates incoming slices in a `Vec<Bytes>` instead of a `VecDeque<u8>`. Replaces calls to `.extend()` and `.drain()` that were quite costly by a simple `concat()` on a vec of slices which is much more optimized
- [x] Hashing (b2, sha256, md5) is now done on a Tokio thread dedicated to cpu-intensive tasks, using `spawn_blocking`
- [x] Block manager now uses 256 independant locks instead of one big lock for writing, reduces contention when writing several/many objects in parallel
- [x] Better LMDB defaults: we now put flags `NoSync` and `NoMetaSync` to avoid `fsync` at each transaction (extremely slow). Also increased number of LMDB readers to accomodate more intensive workloads
Other changes included in this PR:
- [x] Update to hashing and MAC crates: md5 and sha2 from 0.9 to 0.10, hmac from 0.10 to 0.12
- [x] switch to `tracing_subscriber` for logs, which allows to have timing of each event
Reviewed-on: #342
This PR includes work from @jirutka :
- [x] Allow linking against system-provided libraries (libsodium, libsqlite, libzstd) #370
- [x] Make OTLP exporter optional and allow building without Prometheus exporter (/metrics) #372
And also:
- [x] Update `.nix` files
- [x] Remove heed default-features
- [x] Bump versions of all Garage crates to 0.8.0
- [x] Make db engines (lmdb, sled, sqlite) optionnal
- [x] Add documentation for available features
- [x] Directly include code of previous versions used for migration in order to reduce dependencies
- [x] Read variable `GIT_VERSION` from garage main instead of in crate garage_util to make builds faster
- [x] Report features used in the build somewhere? (in `garage --version` or something)
- [x] Check we `warn!` correctly if we try to use deactivated feature
- [x] Allow not to launch S3 endpoint if not in config
Reviewed-on: #373
Garage currently uses the legacy resolver "1". The new one is used
by default if the root package specifies 'edition = 2021', which
Garage does not (yet).
The problem with the legacy resolver is, among others, that features
enabled by dev-dependencies are propagated to normal dependencies.
This affects e.g. hyper - one of the dev-dependencies enables "http2"
feature that adds many extra dependencies. If we build garage without
opentelemetry-otlp (this is enabled in the following commit), there's
no normal dependency enabling "http2" feature.
See https://doc.rust-lang.org/cargo/reference/resolver.html#feature-resolver-version-2
Included in this PR:
- [x] Small refactor, resync code is moved to a separate `block/resync.rs` file
- [x] Block resync tranquility is no longer in config file, it is set dynamically using `garage worker set resync-tranquility` (this parameter is persisted over Garage restarts)
- [x] Up to 4 block resync workers can be activated to run simultaneously to speed up big resyncs, this parameter is set dynamically using `garage worker set resync-n-workers`
Reviewed-on: #369
Unfortunately, rusqlite uses the opposite logic for enabling/disabling
bundled libraries to others (libsodium-sys, zstd-sys). Cargo features
are very limited and doesn't allow to enable feature A in a dependency
iff feature B is disabled.
Note, lmdb-rkv-sys doesn't need any special treatment because it
automatically links against system liblmdb if found via pkgconf.
Linux distros should build garage with
`--no-default-features --features system-libs` to disable bundled-libs
and enable system-libs.
If this feature is enabled, libsodium-sys and zstd-sys will link
dynamically against system-provided libraries instead of building
and linking statically the bundled (possibly outdated and vulnerable)
copies of them. This feature is intended mainly for linux package
maintainers.
