Use MultiLockGuard to guarantee atomicity for multiple keys commands #1700
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In kvrocks, for multiple keys commands, we may break atomicity. such as ZUNION, ZUNIONSTORE, ZINTERSTORE, SUNION, SUNIONSTORE, SINTER, SINTERSTORE, SDIFF and SDIFFSTORE. For SDIFFSTORE destination key1 [key2 ...] command, kvrocks will read key1, key2 ... orderly without any lock, and then restore the diff into destination key. So maybe some keys may be changed when we read them orderly, that breaks atomicity but redis can guarantee atomicity. In this PR, we are using MultiLockGuard to lock these keys before we read or write, so it is impossible to change these keys. Fixes 1692.
mapleFU
previously approved these changes
Aug 25, 2023
Co-authored-by: mwish <maplewish117@gmail.com>
mapleFU
approved these changes
Aug 25, 2023
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In kvrocks, for multiple keys commands, we may break atomicity.
such as
ZUNION,ZUNIONSTORE,ZINTERSTORE,SUNION,SUNIONSTORE,SINTER,SINTERSTORE,SDIFFandSDIFFSTORE.For
SDIFFSTORE destination key1 [key2 ...]command, kvrocks willread key1, key2 ... orderly without any lock, and then restore the
diff into destination key. So maybe some keys may be changed when
we read them orderly, that breaks atomicity but redis can guarantee
atomicity.
In this PR, we are using
MultiLockGuardto lock these keys beforewe read or write, so it is impossible to change these keys. This change
affects all commands listed previously.
Fixes #1692.