Backport to 0.1: Avoid starvation from FuturesUnordered::poll_next #2122
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
This backports rust-lang#2049 to the 0.1 branch. Without this change, polling > 200 futures trough a FuturesUnordered on a Tokio 0.2 executor results in a busy loop in Tokio's cooperative scheduling module. See for a repro of where this breaks: tokio-rs/tokio#2390 Tested by running the reproducer I submitted there. Without this change, it hangs forever (spinning on CPU). With the change, it doesn't.
|
Thanks for the backport! |
Merged
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Outdated suggestions cannot be applied.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.
This backports #2049 to the
0.1 branch. Without this change, polling > 200 futures trough a
FuturesUnordered on a Tokio 0.2 executor results in a busy loop in
Tokio's cooperative scheduling module.
See for a repro of where this breaks:
tokio-rs/tokio#2390
Tested by running the reproducer I submitted there. Without this change,
it hangs forever (spinning on CPU). With the change, it doesn't.