From MySQL 5.7, we had a Multi-threaded Slave (MTS) Applier
LOGICAL_CLOCK to overcome the
problems of parallel replication within a database.
To further improve the parallelisation mechanism, from MySQL 8 (5.7.22) we have write-set replication, so before going further , lets look at the difference between Logical clock (LC) and Writeset.
Transactions that are part of the same binary log group commit on a master are applied in parallel on a slave. The dependencies between transactions are tracked based on their timestamps to provide additional parallelisation where possible.
Write-set is a mechanism to track independent
transactions that can be executed in parallel in the slave.
Parallelising on write sets has potentially much more parallelism
logical_clock ,since it does not depend …