fix: fulfill snapshot promise on leadership change#6141
Open
Qian-Cheng-nju wants to merge 2 commits intovesoft-inc:masterfrom
Open
fix: fulfill snapshot promise on leadership change#6141Qian-Cheng-nju wants to merge 2 commits intovesoft-inc:masterfrom
Qian-Cheng-nju wants to merge 2 commits intovesoft-inc:masterfrom
Conversation
|
|
Author
|
recheck |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Hi, thanks for nebula!
We noticed an issue in SnapshotManager::sendSnapshot() and put together a fix — would appreciate a look when you get a chance.
When sendSnapshot() detects that leadership has changed (line 42-46), it returns early without fulfilling the promise
pcreated at line 33. The promise destructor then triggers a BrokenPromise on the future side, but Host's cleanup code (sendingSnapshot_ = false at line 372-373) is only registered via .thenValue(), so it never runs on error. The Host ends up permanently stuck with sendingSnapshot_=true and can't send anything to that peer anymore.The fix just adds p.setValue(Status::Error("Leader changed")) before the early return.
We also included a standalone reproduction (tests/nb5_snapshot_promise_wedge.cpp) that shows the wedging behavior using std::promise/std::future.