Compact recently-closed heap to prevent stale entry accumulation#134
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Isusami wants to merge 1 commit intomasterking32:mainfrom
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Compact recently-closed heap to prevent stale entry accumulation#134Isusami wants to merge 1 commit intomasterking32:mainfrom
Isusami wants to merge 1 commit intomasterking32:mainfrom
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When stream IDs are rapidly recycled, re-remembering pushes new heap entries while stale ones remain, causing the heap to grow up to ~1.9x the map size. Add compactRecentlyClosedHeapLocked to rebuild the heap from the authoritative map when it exceeds 1.5x, bounding peak memory. Includes regression test TestRecentlyClosedHeapStaleEntryGrowth.
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Summary
Add heap compaction to
pruneRecentlyClosedLockedto prevent unbounded growth of therecentlyClosedHeapwhen stream IDs are rapidly recycled.Changes
compactRecentlyClosedHeapLocked-- rebuilds the heap from the authoritative map when the heap exceeds 1.5x the map size (with a minimum floor ofmapLen + 4)pruneRecentlyClosedLockedcycleTestRecentlyClosedHeapStaleEntryGrowthregression test that simulates 10 cycles of 50 recycled stream IDsWhy
When a stream ID is re-remembered with a new expiration, a new entry is pushed onto the heap but the old (stale) entry remains. The lazy-deletion in
pruneRecentlyClosedLockedonly cleans up entries at the front of the heap. Under pathological stream ID recycling, the heap grew to ~1.9x the map size. With compaction, peak ratio is capped at ~1.5x.Test plan
go test -race ./internal/client/...-- all tests pass, race-cleanTestRecentlyClosedHeapStaleEntryGrowthconfirms heap stays within 1.5x bound