Bug #86079 Deadlock with slave_preserve_commit_order=ON with Bug#86078.
Submitted: 25 Apr 2017 19:28 Modified: 27 Feb 2018 17:32
Reporter: Jean-François Gagné Email Updates:
Status: Closed Impact on me:
Category:MySQL Server: Replication Severity:S2 (Serious)
Version:8.0.1 OS:Any
Assigned to: CPU Architecture:Any

[25 Apr 2017 19:28] Jean-François Gagné

with I was reproducing Bug#86078 to understand more, I ran the slave with slave_preserve_commit_order=ON.  This lead to a deadlock in the SQL_THREAD.  I had the following:

-SHOW SLAVE STATUS shows "Slave_SQL_Running: Yes" with a worker error,
-The worker error is the same as in Bug#86078 (Duplicate entry)

There is no way to stop the slave: a STOP SLAVE hangs and killing the worker do no help (I had to resort to kill -9).

Thanks in advance for looking into this,


How to repeat:
See description.
[15 Jun 2017 4:45] MySQL Verification Team
Thank you Jean, since this is related with Bug #86078, copying this internally as well to keep track of this.

[16 Nov 2017 7:58] Erlend Dahl
Posted by developer:

The issue was not easy to reproduce, but is not reproducible anymore after
BUG#26277771 and BUG#25585436 were fixed.

BUG#26177771 was allowing dependent transactions to be executed in parallel.

BUG#25585436 was making the MTS coordinator to misbehave was asked to stop in
parallel with workers signaling errors.

Fixed in the upcoming release 8.0.4.
[27 Feb 2018 17:32] Jean-François Gagné
A similar problem is identified in Bug#89247.