maria-discuss team mailing list archive

[Kristian Nielsen <knielsen@xxxxxxxxxxxxxxx>]

andrei.elkin@xxxxxxxxxx writes:

> And the above transition can be explained by
> MDEV-24654 GTID event falsely marked transactional, its patch is under
> review.

Oh, yes, this bug sounds like it could result in what Jan described. It was
not clear to me from the bug description exactly under what conditions the
bug occurs, but if the first slave marks the replicated transactions as
"transactional" in its binlog, then the observed behaviour could occur.

The question then is how the chained slaves manage to run MyISAM
transactions in parallel without getting conflicts and hanging. One
possibility is that these are mostly insert-only queries (as Jan mentioned
in another mail), and I believe that MyISAM has the feature that MyISAM can
handle insert-only queries in parallel without locks and conflicts.

Would require a bit more research to be sure this is the explanation, but it
seems a possibility.

 - Kristian.