Skip to content

Akka.Cluster: make Cluster extension startup non-blocking (fixes StressSpec CI deadlock) #8359

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Aaronontheweb merged 3 commits into from
Jul 10, 2026
Merged

Akka.Cluster: make Cluster extension startup non-blocking (fixes StressSpec CI deadlock) #8359

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
1d3c7ad
Akka.Cluster: make Cluster extension startup non-blocking
Aaronontheweb Jul 10, 2026
1848e5a
Merge branch 'dev' into fix/cluster-nonblocking-startup
Aaronontheweb Jul 10, 2026
d8fa2e6
Address slopwatch SW003 findings in ClusterStartupFuzzSpec
Aaronontheweb Jul 10, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions BREAKING_CHANGES_V1.6.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,7 @@ of `Behavior`, `Wire`, `API` (combine with `+`).

| Status | PR / Branch | Component | Type | Change | Migration |
|--------|-------------|-----------|------|--------|-----------|
| Planned | `fix/cluster-nonblocking-startup` | `Akka.Cluster` | Behavior | Cluster extension startup no longer blocks on an internal 20s ask bounded by `akka.actor.creation-timeout`; `Cluster.Get()` returns immediately and core initialization completes asynchronously. The "Failed to startup Cluster" ask-timeout failure mode (which could terminate a healthy node under thread starvation) is removed; genuine core-startup failures still shut the node down via supervision. | None for typical code — all public APIs are message-based or awaitable. Code that used `Cluster.Get()` as a "core is started" synchronization point should await `JoinAsync`/`RegisterOnMemberUp` or observe cluster state. |
| Planned | `fix/artery-pipe-watermarks` | `Akka.Remote` (Artery) | Behavior | Artery TCP connections now raise the pause/resume watermarks of their internal read pipe to 1 MiB (pause 2 MiB), via a new opt-in `Akka.IO.Inet.SO.PipeBufferSize` socket option consulted by `TcpIncomingConnection`/`TcpOutgoingConnection`, configurable via `akka.remote.artery.advanced.tcp.pipe-buffer-size` (default `1m`). Akka.IO's own default (~16 KiB, derived from `akka.io.tcp.receive-buffer-size`) is unchanged for every other TCP connection. | No action required. Artery connections use somewhat more memory per connection and see higher throughput under high-in-flight/one-way traffic; tune via `akka.remote.artery.advanced.tcp.pipe-buffer-size` if needed. |
| Merged | [#8317](https://github.com/akkadotnet/akka.net/pull/8317) | `Akka.Remote` / `Akka.Cluster` | API | System/address UID widened `int` → `long` across `AddressUid.Uid`, `AddressUidExtension.Uid()`, `UniqueAddress(Address, int)`/`.Uid`, `QuarantinedEvent(Address, int)`/`.Uid`, `RemoteWatcher.HeartbeatRsp(int)`/`.AddressUid`, and all `Quarantine(Address, int? uid)` members (`IRemoteActorRefProvider` / `RemoteTransport` / `RemoteWatcher`). Hard re-type (v1.6). Prerequisite for Artery. | Recompile against the `long` members; replace `int` uid locals with `long`. Default UID generation stays in 32-bit range; full 64-bit generation is opt-in via `akka.remote.use-64bit-system-uids = on`. |
| Merged | [#8317](https://github.com/akkadotnet/akka.net/pull/8317) | `Akka.Cluster` | Wire | Cluster gossip `UniqueAddress.uid` widened `uint32` → `uint64` (`ClusterMessages.proto`). Same varint wire type → binary-compatible for uids ≤ `uint32.MaxValue`. | Rolling upgrade safe provided uid generation stays in 32-bit range (the default); enable `akka.remote.use-64bit-system-uids` only after the whole cluster + all remote peers are on v1.6. |
Expand Down
Loading
Loading