Improve push lock wakeup behavior under contention - #38
Merged
Conversation
Owner
|
Thanks for the PR! Sorry it took this long to review, I was quite focused on getting wi-fi to work in Astral (I am giving a talk about Astral next month and I want to talk about the wi-fi stack in it) |
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
The current implementation doesn't record whether a waiter requested shared or exclusive ownership, so every release wakes only one waiter. As a result, shared waiters queued behind an exclusive owner are effectively serialized.
This change records waiter mode and wakes the waiter chain when the oldest waiter is shared, while preserving retry-after-wake semantics. Also removes hard coded push lock masks/alignment values.
Queued 4 reader case:
max-active=1, ~83 msmax-active=4, ~21-22 ms