* rust volume: honour is_last in the tail sender instead of rescanning
volume_tail_sender discarded the is_last flag from
binary_search_by_append_at_ns:
Ok((offset, _is_last)) => {
if offset.is_zero() { Ok(sb_size) } ...
is_last means the caller is already caught up. Go answers that with a
heartbeat and does not scan at all (volume_grpc_tail.go, `if isLastOne`).
Dropping it is expensive rather than untidy, because the branches interact:
when the search reports caught-up it returns Offset::default(), which is
zero, so the start offset falls back to sb_size -- the beginning of the
data -- and scan_raw_needles_from materialises every needle from there to
EOF into a Vec. The timestamp filter discards all of it, the loop sleeps
2s, and it happens again.
A volume being moved is marked read-only before the copy, so it is ALWAYS
caught up during the tail phase. Measured on one volume.move of a 2.15 GB
volume, sampling the source's cgroup anon every 2s against the move's own
phase output:
copying 16 -> 37 MB CopyFile streams correctly, stays bounded
tailing 904 -> 2166 -> 629 -> 2166 -> 342 -> 2173 -> 2179 MB
deleting 46 MB
Six full-volume allocate/free cycles in 35s, peak 2179 MB against a volume
of 2147 MiB. The destination never exceeded 35 MB, so this is entirely
source-side. Under a per-process memory cap it OOM-kills the source
whenever the volume exceeds the cap.
The ordering here is the whole fix and is easy to get wrong: resolve the
start offset and is_last under a brief lock, return the heartbeat
immediately when caught up, and only then reach the scan. An earlier cut
set the flag correctly but placed the early return after the block that
performs the scan -- the heartbeat fired and the destination received
nothing, yet every iteration still read the whole volume and discarded it.
Production showed no improvement (1770 MB across five cycles), which is
what caught it. The binary search is over the .idx and costs nothing; the
scan is the expensive part and must not run speculatively.
Three tests, and the last two matter as much as the first: a fix that
always reported "caught up" would make tailing silently lose needles, a
worse bug than the one being fixed. One asserts is_last for a caller at or
beyond the newest append_at_ns; one asserts NOT is_last for a caller that
is behind, so real tail data is still scanned and shipped; one asserts NOT
is_last when the only newer record is a delete, and that scanning from the
returned offset ships exactly that tombstone.
Left deliberately unfixed, and worth separate changes: the scan still
collects into a Vec rather than streaming through a visitor as Go's
ScanVolumeFileFrom does, and it runs while holding store.read(), the same
lock-across-a-large-read shape as #11235. Both are latent once the rescan
is gone, since remaining scans are bounded by genuinely new data.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MFr2v4BUqrXdgj4LEUAwVF
Claude-Session: https://claude.ai/code/session_018VF7E9SHPihG1jC1grU9H3
* rust volume: resolve and scan the tail under one store guard
The tail sender took store.read() once for the binary search and again
for the scan. A vacuum commit takes the store write lock and swaps
.dat/.idx, so it could land between the two: the offset resolved against
the old files would then be applied to the new ones and start the scan
inside an unrelated record. The code before the is_last fix held a
single guard for both. Restore that, and scan only when the caller is not
caught up, so the caught-up heartbeat still skips the scan and is sent
outside the lock.
Also pin the compacted-volume boundary raised in review. Compaction
writes .idx in needle-id order in both Go and Rust, so the search can
report caught-up while an earlier row is newer; such a caller's since_ns
is the last row's timestamp, so those rows were in the files it copied.
A write made afterwards is appended as the final row, which the search
cannot step past. The new test asserts it still reaches the scan.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018VF7E9SHPihG1jC1grU9H3
* rust volume: make the compaction tail test a genuine overwrite
The compaction regression test's second id=1 write reused the first
write's data, so write_needle's dedup short-circuit (is_file_unchanged)
returned without appending or updating append_at_ns. Compaction then
kept key 1's original (older) timestamp, so the test passed without
exercising the overwrite it describes -- key 2 was the final row only
because key 1 was never actually newer.
Give the overwrite distinct data so it appends a new record, and assert
key1_ns > key2_ns up front so a future dedup regression fails the test
instead of silently hollowing it out. Trim the verbose comments on the
tail sender and the binary-search tests to their essentials.
---------
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Chris Lu <chris.lu@gmail.com>
SeaweedFS Volume Server (Rust)
A drop-in replacement for the SeaweedFS Go volume server, rewritten in Rust. It uses binary-compatible storage formats (.dat, .idx, .vif) and speaks the same HTTP and gRPC protocols, so it works with an unmodified Go master server.
Building
Requires Rust 1.91.1+ (2024 edition), matching rust-version in Cargo.toml.
The patch release matters: 1.91.0 does not build. The edition itself only needs
1.85; the higher floor comes from the dependency tree — chiefly the AWS SDK — so
it moves with those crates. CI builds on the latest stable.
cd seaweed-volume
cargo build --release
The binary is produced at target/release/seaweed-volume.
Running
Start a Go master server first, then point the Rust volume server at it:
# Minimal
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7
# Multiple data directories
seaweed-volume --port 8080 --master localhost:9333 \
--dir /mnt/ssd1,/mnt/ssd2 --max 100,100 --disk ssd
# With datacenter/rack topology
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
--dataCenter dc1 --rack rack1
# With JWT authentication
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
--securityFile /etc/seaweedfs/security.toml
# With TLS (configured in security.toml via [https.volume] and [grpc.volume] sections)
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
--securityFile /etc/seaweedfs/security.toml
Common flags
| Flag | Default | Description |
|---|---|---|
--port |
8080 |
HTTP listen port |
--port.grpc |
port+10000 |
gRPC listen port |
--master |
localhost:9333 |
Comma-separated master server addresses |
--dir |
/tmp |
Comma-separated data directories |
--max |
8 |
Max volumes per directory (comma-separated) |
--ip |
auto-detect | Server IP / identifier |
--ip.bind |
same as --ip |
Bind address |
--dataCenter |
Datacenter name | |
--rack |
Rack name | |
--disk |
Disk type tag: hdd, ssd, or custom |
|
--index |
memory |
Needle map type: memory, leveldb, leveldbMedium, leveldbLarge |
--readMode |
proxy |
Non-local read mode: local, proxy, redirect |
--fileSizeLimitMB |
256 |
Max upload file size |
--minFreeSpace |
1 (percent) |
Min free disk space before marking volumes read-only |
--securityFile |
Path to security.toml for JWT keys and TLS certs |
|
--metricsPort |
0 (disabled) |
Prometheus metrics endpoint port |
--whiteList |
Comma-separated IPs with write permission | |
--preStopSeconds |
10 |
Graceful drain period before shutdown |
--compactionMBps |
0 (unlimited) |
Compaction I/O rate limit |
--pprof |
false |
Enable pprof HTTP handlers |
Set RUST_LOG=debug (or trace, info, warn) for log level control.
Set SEAWEED_WRITE_QUEUE=1 to enable batched async write processing.
Features
- Binary compatible -- reads and writes the same
.dat/.idx/.viffiles as the Go server; seamless migration with no data conversion. - HTTP + gRPC -- full implementation of the volume server HTTP API and all gRPC RPCs including streaming operations (copy, tail, incremental copy, vacuum).
- Master heartbeat -- bidirectional streaming heartbeat with the Go master server; volume and EC shard registration, leader failover, graceful shutdown deregistration.
- JWT authentication -- signing key configuration via
security.tomlwith token source precedence (query > header > cookie), file_id claims validation, and separate read/write keys. - TLS -- HTTPS for the HTTP API and mTLS for gRPC, configured through
security.toml. - Erasure coding -- Reed-Solomon EC shard management: mount/unmount, read, rebuild, copy, delete, and shard-to-volume reconstruction.
- S3 remote storage --
FetchAndWriteNeedlereads from any S3-compatible backend (AWS, MinIO, Wasabi, Backblaze, etc.) and writes locally. SupportsVolumeTierMoveDatToRemote/FromRemotefor tiered storage. - Needle map backends -- in-memory HashMap, LevelDB (via
rusty-leveldb), or redb (pure Rust disk-backed) needle maps. - Image processing -- on-the-fly resize/crop, JPEG EXIF orientation auto-fix, WebP support.
- Streaming reads -- large files (>1MB) are streamed via
spawn_blockingto avoid blocking the async runtime. - Auto-compression -- compressible file types (text, JSON, CSS, JS, SVG, etc.) are gzip-compressed on upload.
- Prometheus metrics -- counters, histograms, and gauges exported at a dedicated metrics port; optional push gateway support.
- Graceful shutdown -- SIGINT/SIGTERM handling with configurable
preStopSecondsdrain period.
Testing
Rust unit tests
cd seaweed-volume
cargo test
Go integration tests
The Go test suite can target either the Go or Rust volume server via the VOLUME_SERVER_IMPL environment variable:
# Run all HTTP + gRPC integration tests against the Rust server
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 1200s \
./test/volume_server/grpc/... ./test/volume_server/http/...
# Run a single test
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 60s \
-run "TestName" ./test/volume_server/http/...
# Run S3 remote storage tests
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 180s \
-run "TestFetchAndWriteNeedle" ./test/volume_server/grpc/...
Load testing
A load test harness is available at test/volume_server/loadtest/. See that directory for usage instructions and scenarios.
Architecture
The server runs three listeners concurrently:
- HTTP (Axum 0.7) -- admin and public routers for file upload/download, status, and stats endpoints.
- gRPC (Tonic 0.12) -- all
VolumeServerRPCs from the SeaweedFS protobuf definition. - Metrics (optional) -- Prometheus scrape endpoint on a separate port.
Key source modules:
| Path | Description |
|---|---|
src/main.rs |
Entry point, server startup, signal handling |
src/config.rs |
CLI parsing and configuration resolution |
src/server/volume_server.rs |
HTTP router setup and middleware |
src/server/handlers.rs |
HTTP request handlers (read, write, delete, status) |
src/server/grpc_server.rs |
gRPC service implementation |
src/server/heartbeat.rs |
Master heartbeat loop |
src/storage/volume.rs |
Volume read/write/delete logic |
src/storage/needle.rs |
Needle (file entry) serialization |
src/storage/store.rs |
Multi-volume store management |
src/security.rs |
JWT validation and IP whitelist guard |
src/remote_storage/ |
S3 remote storage backend |
See DEV_PLAN.md for the full development history and feature checklist.