maria-discuss team mailing list archive

[Jan Křístek <jkresa@xxxxxxxxx>]

Hi,

We have a MariaDB 10.3 replication setup with one master and a few chained
slaves (each has log_slave_updates switched on). Master uses mainly MyISAM
tables, slaves have about 10 or 40 threads for parallel replication.

Interesting is, that the first slave in the chain counts replicated
statements into Non-Transactional Groups and the following ones count them
into Transactional Groups.

Also, when checking process lists it seems that just one statement is being
processed at the time (of the many threads) on the first slave, while there
are multiple slave replication statements being executed on the 2nd and
following slaves.

Please, does anyone know the reason why the replicated statements are
counted into different groups? Or, more importantly, how to increase the
parallelism on the first slave in the chain?

Thank you for any help.
Jan