Fix json_stats mutexes test for configurable MALLCTL_ARENAS_ALL#9
Merged
jimwwalker merged 1 commit intoJul 7, 2026
Merged
Conversation
test_json_stats_mutexes hard-coded the arena index 4096 in the mallctl name "stats.arenas.4096.mutexes...", assuming MALLCTL_ARENAS_ALL == 4096. That holds only for the default tcache limit. Our downstream --with-lg-tcache-limit patch makes MALLCTL_ARENAS_ALL a configure-computed value of 2^(24 - limit): at the limit=15 we build with, it is 512, not 4096. The test then queried a non-existent arena index and mallctl returned ENOENT, failing every assertion in the merged-arena mutex loop. Stringify the MALLCTL_ARENAS_ALL macro instead of hard-coding the value, matching the usage documented in jemalloc_macros.h. The test now passes for any --with-lg-tcache-limit setting; the change is test-only and does not affect the library.
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
test_json_stats_mutexes hard-coded the arena index 4096 in the mallctl name "stats.arenas.4096.mutexes...", assuming MALLCTL_ARENAS_ALL == 4096. That holds only for the default tcache limit. Our downstream --with-lg-tcache-limit patch makes MALLCTL_ARENAS_ALL a configure-computed value of 2^(24 - limit): at the limit=15 we build with, it is 512, not 4096. The test then queried a non-existent arena index and mallctl returned ENOENT, failing every assertion in the merged-arena mutex loop.
Stringify the MALLCTL_ARENAS_ALL macro instead of hard-coding the value, matching the usage documented in jemalloc_macros.h. The test now passes for any --with-lg-tcache-limit setting; the change is test-only and does not affect the library.