Hi Herve, thanks for your response. Since I'm using Antelope release, the mariadb version is slightly older and checking this variable value it is turned off $ docker exec -it mariadb mariadb -V mariadb Ver 15.1 Distrib 10.11.11-MariaDB, for debian-linux-gnu (x86_64) using EditLine wrapper MariaDB [(none)]> show session variables like '%snapshot%'; +---------------------------+-------+ | Variable_name | Value | +---------------------------+-------+ | innodb_snapshot_isolation | OFF | +---------------------------+-------+ I don't think this could be the root cause of the problem, but thank you for the reply! I'm still digging in on the problem to find a possible root cause. Regards. Em ter., 15 de jul. de 2025 às 05:55, Herve Beraud <hberaud@redhat.com> escreveu:
Hello,
Not sure if this is the root cause of your problem, but that could: - https://mariadb.com/resources/blog/isolation-level-violation-testing-and-deb... - https://jira.mariadb.org/browse/MDEV-35124
End of last week we noticed strange behaviours due to this new transactional model, see https://bugs.launchpad.net/nova/+bug/2116186/.
Le lun. 14 juil. 2025 à 19:43, Winicius Allan <winiciusab12@gmail.com> a écrit :
Hi community o/
Suddenly, I noticed that the login on the dashboard wasn't working, so I checked the keystone logs. I saw some entries like that:
2025-07-10 00:53:45.120 23 ERROR sqlalchemy.pool.impl.QueuePool oslo_db.exception.DBDeadlock: (pymysql.err.OperationalError) (1205, 'Lock wait timeout exceeded; try restarting transaction')
Nova-conductor was also showing messages like these.
At the same time, blazer-manager was logging after every _process_event calling:
ERROR sqlalchemy.exc.TimeoutError: QueuePool limit of size 1 overflow 50 reached, connection timed out, timeout 30.00
I do not know if it's related to the _process_event method that batches events concurrently[1], and the DB was locked. Well... I increased the max_pool_size from 1 to 2 on blazar-manager, and that message stops showing. Does anyone know what can cause this deadlock generally?
I'd like to ask another question: I have three controllers in my environment. Why do controllers with no active VIP address bind connections on the MySQL port, for example:
tcp ESTAB 0 0 10.0.0.105:3306 10.0.0.107:50642 users:(("mariadbd",pid=977010,fd=1089))
[1] https://github.com/openstack/blazar/blob/stable/2024.1/blazar/manager/servic...
Best regards.
-- Hervé Beraud Principal Software Engineer at Red Hat irc: hberaud https://github.com/4383/