Conversation
Starlark map_each repeatedly registers and restores the current thread. Cache its native ID in the JNI entrypoint to avoid repeated syscalls; leave the asynchronous signal handler unchanged.
github-actions
Bot
added
team-Starlark-Interpreter
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
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Description
Cache the native thread ID in
CpuProfilerNativeSupportImpl.getThreadIdusing a function-localthread_localconstant. Keepgettid()uncached becauseonsigprofalso calls it, so the signal handler never initializes thread-local storage.Motivation
Starlark
map_eachrepeatedly registers and restores the current thread. Caching the native thread ID avoids a system call on each registration.In an action that generates a large number of mapped arguments to
ctx.actions.argswith Starlark profiling enabled, median argument expansion fell from 6.552s to 5.850s.Build API Changes
No.
Release Notes
RELNOTES: None