# MY-014054 warnings logged during backup **URL:** \ **Category:** Percona XtraBackup\ **Created:** [May 9, 2024, 4:12am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159 "2024-05-09T04:12:42Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![kevinUU](https://avatars.discourse-cdn.com/v4/letter/k/d2c977/32.png) [@kevinUU](https://forums.percona.com/u/kevinUU)\ **Post date:** [May 9, 2024, 4:12am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/1 "2024-05-09T04:12:43Z")
Hi all, I’m running MySQL 8.0.35 on RHEL 8.8 and am using Xtrabackup 8.0.34-29. When I run a backup using the following command: xtrabackup --backup --target-dir=${BACKUPDIR} --compress I get the following warnings dumped to /var/log/mysqld.log and performance\_schema.error\_log: 2024-05-08T20:01:48.333785+10:00 7 [Warning] [MY-014054] [Repl] Could not purge binary logs since another session is executing LOCK INSTANCE FOR BACKUP. Wait for that session to release the lock. 2024-05-08T20:01:48.333980+10:00 7 [Warning] [MY-014054] [Repl] Could not purge binary logs since another session is executing LOCK INSTANCE FOR BACKUP. Wait for that session to release the lock. It looks like the backup is triggering a binary log switch which then triggers a purge which is failing. Looking at the date stamps on the binary logs, I see this happens during every backup (daily @ 8pm) and the file date stamp matches the error\_log messages: -rw-r-----. 1 mysql mysql 501M May 7 17:00 /var/lib/mysql/mysql-bin.005354 -rw-r-----. 1 mysql mysql 367M May 7 20:01 /var/lib/mysql/mysql-bin.005355 -rw-r-----. 1 mysql mysql 501M May 7 22:09 /var/lib/mysql/mysql-bin.005356 -rw-r-----. 1 mysql mysql 501M May 8 03:58 /var/lib/mysql/mysql-bin.005357 -rw-r-----. 1 mysql mysql 501M May 8 07:49 /var/lib/mysql/mysql-bin.005358 -rw-r-----. 1 mysql mysql 501M May 8 09:08 /var/lib/mysql/mysql-bin.005359 -rw-r-----. 1 mysql mysql 501M May 8 10:32 /var/lib/mysql/mysql-bin.005360 -rw-r-----. 1 mysql mysql 501M May 8 11:53 /var/lib/mysql/mysql-bin.005361 -rw-r-----. 1 mysql mysql 501M May 8 13:12 /var/lib/mysql/mysql-bin.005362 -rw-r-----. 1 mysql mysql 501M May 8 14:46 /var/lib/mysql/mysql-bin.005363 -rw-r-----. 1 mysql mysql 501M May 8 16:34 /var/lib/mysql/mysql-bin.005364 -rw-r-----. 1 mysql mysql 418M May 8 20:01 /var/lib/mysql/mysql-bin.005365 -rw-r-----. 1 mysql mysql 501M May 8 23:25 /var/lib/mysql/mysql-bin.005366 -rw-r-----. 1 mysql mysql 501M May 9 06:33 /var/lib/mysql/mysql-bin.005367 Checking the backup log file, there doesn’t seem to be any indication of an issue or a log switch. This occurs on all of our MySQL servers (4 production and 7 non-production). Is there any way to prevent these warnings? ---
**Author:** ![kevinUU](https://avatars.discourse-cdn.com/v4/letter/k/d2c977/32.png) [@kevinUU](https://forums.percona.com/u/kevinUU)\ **Post date:** [May 9, 2024, 4:46am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/3 "2024-05-09T04:46:56Z")
Thanks David. Are you saying that another session, apart from the backup job, holds a LOCK INSTANCE FOR BACKUP? ---
**Author:** ![kevinUU](https://avatars.discourse-cdn.com/v4/letter/k/d2c977/32.png) [@kevinUU](https://forums.percona.com/u/kevinUU)\ **Post date:** [May 9, 2024, 5:05am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/5 "2024-05-09T05:05:31Z")
Sorry, but I don’t think that’s the case. We are definitely running only one backup process at a time. Also, I tested this on a test server just now, with no other sessions connected. The only session is my ssh connection which runs the backup. If I run the same backup command on this server I get the same ‘MY-014054’ warning logged. ---
**Author:** ![matthewb](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/matthewb/32/34_2.png) [@matthewb](https://forums.percona.com/u/matthewb)\ **Post date:** [May 9, 2024, 12:43pm UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/6 "2024-05-09T12:43:30Z")
Hey @kevinUU, What you do you have set for the following parameters? > binlog\_expire\_logs\_seconds > expire\_logs\_days > max\_binlog\_size What I suspect is happening is that MySQL is trying to rotate/purge your binary logs due to a variable configuration, but it cannot do that because PXB is currently doing a backup. I would suggest increasing either the expiration time, or max size and try the backup again. ---
**Author:** ![kevinUU](https://avatars.discourse-cdn.com/v4/letter/k/d2c977/32.png) [@kevinUU](https://forums.percona.com/u/kevinUU)\ **Post date:** [May 9, 2024, 9:35pm UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/7 "2024-05-09T21:35:09Z")
Thanks @matthewb binlog\_expire\_logs\_seconds=259200 expire\_logs\_days=0 max\_binlog\_size=524288000 However, would MySQL rotate the logs exactly at the time the backup runs every night at 8pm? Also, you can see in my first post that the size of the binlogs that are rotated when the backup starts are smaller than the others. This says to me that even though the max\_binlog\_size hasn’t been reached, the backup forces a rotate? ---
**Author:** ![matthewb](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/matthewb/32/34_2.png) [@matthewb](https://forums.percona.com/u/matthewb)\ **Post date:** [May 10, 2024, 1:08am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/8 "2024-05-10T01:08:13Z")
> [@kevinUU](#): > > This says to me that even though the max\_binlog\_size hasn’t been reached, the backup forces a rotate? That’s correct, PXB does FLUSH BINARY LOGS to rotate to the next log. ---
**Author:** ![kevinUU](https://avatars.discourse-cdn.com/v4/letter/k/d2c977/32.png) [@kevinUU](https://forums.percona.com/u/kevinUU)\ **Post date:** [May 10, 2024, 1:24am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/9 "2024-05-10T01:24:14Z")
So the backup flushes the binary logs which initiates a purge which fails because the instance has been locked for backup? ---
**Author:** ![matthewb](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/matthewb/32/34_2.png) [@matthewb](https://forums.percona.com/u/matthewb)\ **Post date:** [May 10, 2024, 3:16am UTC](https://forums.percona.com/t/my-014054-warnings-logged-during-backup/30159/10 "2024-05-10T03:16:52Z")
PXB does not purge any binlogs, so MySQL is attempting to do that. I see your expire time is only 3 days, and your original post shows 3 day old binlogs. Try increasing the expire time, or do a manual ‘PURGE BINARY LOGS TO ‘xxxx’’ before you do the backup and see if that resolves the issue.