MemPostings.Delete(): make pauses to unlock and let the readers read … #1
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…rometheus#15242) This introduces back some unlocking that was removed in prometheus#13286 but in a more balanced way, as suggested by @pracucci. For TSDBs with a lot of churn, Delete() can take a couple of seconds, and while it's holding the mutex, reads and writes are blocked waiting for that mutex, increasing the number of connections handled and memory usage. This implementation pauses every 4K labels processed (note that also compared to prometheus#13286 we're not processing all the label-values anymore, but only the affected ones, because of prometheus#14307), makes sure that it's possible to get the read lock, and waits for a few milliseconds more. Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com> Co-authored-by: Marco Pracucci <marco@pracucci.com>
This was referenced Dec 11, 2024
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…(prometheus#15242)
This introduces back some unlocking that was removed in prometheus#13286 but in a more balanced way, as suggested by @pracucci.
For TSDBs with a lot of churn, Delete() can take a couple of seconds, and while it's holding the mutex, reads and writes are blocked waiting for that mutex, increasing the number of connections handled and memory usage.
This implementation pauses every 4K labels processed (note that also compared to prometheus#13286 we're not processing all the label-values anymore, but only the affected ones, because of prometheus#14307), makes sure that it's possible to get the read lock, and waits for a few milliseconds more.