vinyl: fix bugs in read iterator#10122
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locker merged 2 commits intotarantool:masterfrom Jun 13, 2024
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If a run iterator is positioned at a non-terminal statement (UPSERT or UPDATE), `vy_run_iterator_next()` will iterate over older statements with the same key using `vy_run_iterator_next_lsn()` to build the key history. While doing so, it may reach the end of the run file (if the current key is the last in the run). This would stop iteration permanently, which is apparently wrong for reverse iterators (LE or LT): if this happens the run iterator won't return any keys preceding the last one in the run file. Fix this by removing `vy_run_iterator_stop()` from `vy_run_iterator_next_lsn()`. Part of tarantool#10109 NO_DOC=bug fix NO_CHANGELOG=next commit
The tuple cache doesn't store older tuple versions so if a reader is in a read view, it must skip tuples that are newer than the read view, see `vy_cache_iterator_stmt_is_visible()`. A reader must also ignore cached intervals if any of the tuples used as a boundary is invisible from the read view, see `vy_cache_iterator_skip_to_read_view()`. There's a bug in `vy_cache_iterator_restore()` because of which such an interval may be returned to the reader: when we step backwards from the last returned tuple we consider only one of the boundaries. As a result, if the other boundary is invisible from the read view, the reader will assume there's nothing in the index between the boundaries and skip reading older sources (memory, disk). Fix this by always checking if the other boundary is visible. Closes tarantool#10109 NO_DOC=bug fix
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lenkis
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Jun 11, 2024
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Cherry-picked to 2.11 and 3.1. |
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The PR fixes a couple of bugs in the read iterator because of which tuples written to the database could be skipped by a range
select.Closes #10109