internal: Improve the Iter performance of LockMap on empty maps#2127
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ajgajg1134
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July 19, 2023 15:54
BenchmarksBenchmark execution time: 2023-07-19 15:59:01 Comparing candidate commit 5b7943f in PR branch Found 0 performance improvements and 0 performance regressions! Performance is the same for 27 metrics, 0 unstable metrics. |
knusbaum
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Jul 19, 2023
ajgajg1134
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Jul 19, 2023
Turns out doing RLock and RUnlock can still be slow especially when this code is in a HOT path. For most users this map will be empty. Therefore it's worth speeding up that case at the cost of a tiny bit of extra memory and a bit of complexity.
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knusbaum
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Jul 20, 2023
Turns out doing RLock and RUnlock can still be slow especially when this code is in a HOT path. For most users this map will be empty. Therefore it's worth speeding up that case at the cost of a tiny bit of extra memory and a bit of complexity. Cherry-picks across #2127
katiehockman
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Jul 26, 2023
Turns out doing RLock and RUnlock can still be slow especially when this code is in a HOT path. For most users this map will be empty. Therefore it's worth speeding up that case at the cost of a tiny bit of extra memory and a bit of complexity. Cherry-picks across #2127
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What does this PR do?
Improves
LockMap.Iterperformance for empty mapsMotivation
Turns out doing RLock and RUnlock can still be slow especially when this code is in a HOT path. For most users this map will be empty. Therefore it's worth speeding up that case at the cost of a tiny bit of extra memory and a bit of complexity.
Describe how to test/QA your changes
Added a thrash test that when run with the race detector should help make sure we don't miss anything (and it verifies that the count and len match at the end to make sure they don't get out of sync).
Reviewer's Checklist