Fix VREM of disk-evicted Vector Set element spuriously reporting not-found#1961
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tiagonapoli wants to merge 3 commits into
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Fix VREM of disk-evicted Vector Set element spuriously reporting not-found#1961tiagonapoli wants to merge 3 commits into
tiagonapoli wants to merge 3 commits into
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…found The DiskANN delete callback (DeleteCallbackUnmanaged) gated its return on status.Found. Tsavorite deletes are tombstone appends that never read the old record back, so for a record already flushed to disk status.Found is false even though the key logically exists. That made the callback return 0, Service.Remove return false, TryRemove report MissingElement, and VREM answer :0 (silently, with no error) for any element that had been evicted to disk. Return success on status.IsCompletedSuccessfully, matching the sibling Write/RMW callbacks. Adds two layered regression tests: an end-to-end VREM-over-RESP test and a lower-level test that drives VectorManager.TryRemove/Service.Remove directly, both forcing the element to disk via Log.FlushAndEvict first. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 1030a670-b85f-41bb-b225-e2ddef5535eb
Drop the SeedVectorSetAndFlushToDisk helper in favor of three hardcoded VADD VALUES calls plus an inline FlushAndEvict per test. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 1030a670-b85f-41bb-b225-e2ddef5535eb
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 1030a670-b85f-41bb-b225-e2ddef5535eb
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Problem
VREMof a Vector Set element silently reported "not removed" (:0, no error) whenever that element's records had been evicted to disk.The DiskANN delete callback (
VectorManager.DeleteCallbackUnmanaged) gated its return value onstatus.Found. Tsavorite deletes are tombstone appends and never read the old record back, so for a disk-resident recordstatus.Found == falseeven though the key logically exists. The failing0then propagated:DeleteCallbackUnmanagedreturns0→ nativeremove!= 1 →DiskANNService.Removefalse→VectorManager.TryRemove->MissingElement→NetworkVREMwrites:0.The client could not distinguish this from "element was never there" — a data-correctness bug with no exception.
Fix
Return success on
status.IsCompletedSuccessfully(dropping the&& status.Found), matching the siblingWrite/RMWcallbacks which already only checkIsCompletedSuccessfully.Tests
Two layered regression tests, both forcing every record to disk via
Log.FlushAndEvictfirst:VREMOnDiskFlushedElementSucceeds— end-to-end over RESP: assertsVREMreturns1, a repeat returns0, and aVSIMconsistency check.VREMOnDiskFlushedElement_ServiceRemoveSucceeds— lower-level: drivesVectorManager.TryRemove→DiskANNService.Removedirectly (bypassing RESP parsing/encoding and AOF replication), assertingVectorManagerResult.OK.Verified before/after by toggling the fix:
VREM)1Expected: 1, But was: 0Service.Remove(TryRemove)OKExpected: OK, But was: MissingElement