Start process_queue_thread when dead #148
Merged
Conversation
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
dalehamel
approved these changes
Dec 23, 2024
Member
dalehamel
left a comment
dalehamel
left a comment
There was a problem hiding this comment.
solid debugging of a gnarly edge case 👏
| end | ||
|
|
||
| def process_queue_thread | ||
| @process_queue_thread ||= Thread.new do |
Member
There was a problem hiding this comment.
so this line here is the root of the bug right? This variable is bound already, but the thread is dead, so we call this method but it returns and a new thread is never started
| assert(th.alive?) | ||
| end | ||
|
|
||
| test "process_queue_thread is recreated on enqueue if stopped" do |
Member
There was a problem hiding this comment.
I assume this tests fails on the old code right? Just to be 100% sure it's a good regression test
Contributor
Author
There was a problem hiding this comment.
Yes I tested that. Had to add th.join as kill is not instant and the failure was flaky.
manuelfelipe
approved these changes
Jan 8, 2025
Member
manuelfelipe
left a comment
manuelfelipe
left a comment
There was a problem hiding this comment.
thanks for the fix and the troubleshooting efforts. Fix makes sense when considering our forking strategy
Contributor
Author
|
tested this in production - fix works. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 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Outdated suggestions cannot be applied.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.
Fixes the case when process A starts the background thread and process B is forked from process A. In this case, the old code would not recreate the thread because the thread variable is still there but the thread itself is dead.
We see this a lot in pitchfork because workers are forked from
mold, which I believe/understand is selected from a worker too.