vinyl: disable tautological DELETE optimization for deferred DELETEs#10910
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locker merged 1 commit intotarantool:masterfrom Dec 11, 2024
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If the write iterator sees that one DELETE statement follows another, which isn't discarded because it's referenced by a read view, it drops the newer DELETE, see commit a6f45d8 ("vinyl: discard tautological DELETEs on compaction"). This is incorrect if the older DELETE is a deferred DELETE statement (marked as SKIP READ) because such statements are dumped out of order, i.e. there may be a statement with the LSN lying between the two DELETEs in an older source not included into this compaction task. If we discarded the newer DELETE, we wouldn't overwrite this statement on major compaction, leaving garbage. Fix this issue by disabling this optimization for deferred DELETEs. Closes tarantool#10895 NO_DOC=bug fix
xuniq
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Dec 11, 2024
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Cherry-picked to 2.11, 3.2, 3.3. |
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If the write iterator sees that one DELETE statement follows another, which isn't discarded because it's referenced by a read view, it drops the newer DELETE, see commit a6f45d8 ("vinyl: discard tautological DELETEs on compaction"). This is incorrect if the older DELETE is a deferred DELETE statement (marked as SKIP READ) because such statements are dumped out of order, i.e. there may be a statement with the LSN lying between the two DELETEs in an older source not included into this compaction task. If we discarded the newer DELETE, we wouldn't overwrite this statement on major compaction, leaving garbage. Fix this issue by disabling this optimization for deferred DELETEs.
Closes #10895