Fix SeekForPrev key pinning regression in FindValueForCurrentKeyUsingSeek#14746
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mszeszko-meta wants to merge 1 commit into
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Fix SeekForPrev key pinning regression in FindValueForCurrentKeyUsingSeek#14746mszeszko-meta wants to merge 1 commit into
mszeszko-meta wants to merge 1 commit into
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@mszeszko-meta merged this pull request in 3daabe2. |
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Summary
In PR #13531, we added a
saved_key_.SetUserKey(ikey.user_key)call inFindValueForCurrentKeyUsingSeekto fix unprepared-value reverse iteration. The defaultcopy=trueparameter unconditionally copies the key into the internal buffer, breaking is-key-pinned whenpin_data=true. This path triggers only when a key has more versions thanmax_sequential_skip_in_iterations(default 8), making the bug rare and hard to repro deterministically.Fix: pass
!pin_thru_lifetime_ || !iter_.iter()->IsKeyPinned()as the copy parameter, matching every otherSetUserKeycall site inDBIter.Test Plan
New test
SeekForPrevKeyPinnedWithManyVersions: writes 20 versions of the same key, confirmsFindValueForCurrentKeyUsingSeekis taken viaNUMBER_OF_RESEEKS_IN_ITERATION, asserts is-key-pinned == "1" afterSeekForPrev. Fails without fix, passes with.