[release/9.0-staging] DATAS BGC thread synchronization fix #110174
Merged
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Outdated suggestions cannot be applied.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.
Backport of #109804 to release/9.0-staging
/cc @mangod9 @mrsharm
Customer Impact
Original issue: #109804. Customers discovered a hang because one of the BGC threads had disappeared which shouldn't have happened - this is due to a BGC thread that was not needed during a previous BGC (because DATAS only needed a subset of BGC threads for that BGC to run) ran at a time when
settings.concurrent
was FALSE so it exited.Regression
Testing
I have added stress code in GC (under
STRESS_DYNAMIC_HEAP_COUNT
) to make the repro quite easy.Risk
Low. This has gone through extensive testing on both Windows and Linux.