With multi-threaded replication (MTR), a replica can commit
transactions in the same order as the source, or not. This is
determined by sysvar replica_preserve_commit_order
(RPCO). As of MySQL v8.0.27 (released October 2021) it’s ON by
default, but it was OFF by default for several years prior. In
either case, it’s relatively new compared to 20+ years of
single-threaded replication for which commit order was not an
issue or option. But with MTR, it’s important to understand the
affects of RPCO, especially with respect to the focus of this
three-part series: replication lag.
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Nov
22
2024
Showing entries 1 to 1