My mysql server has started crashing intermittently

MySQL & MariaDB
1

Server crashes, and restarts. This entry occurs in the syslog immediately before the crash:

kernel: audit: type=1400 audit(1738811012.496:50): apparmor==“DENIED” operation=“open” profile=“/usr/sbin/mysqld” name=“/proc/29800/task/29890/mem” pid=29800 comm=“mysqld” requested_mask=“r” denied_mask=“r” fsuid=111 ouid=111

Am I right in thinking that this is a out of memory problem?

This is the mysql error log:
mysqld got signal 11 ;
…
key_buffer_size=268435456
read_buffer_size=1048576
max_used_connections=431
max_threads=1000
thread_count=8
connection_count=8
…
Thread pointer: 0x7f87380ce7e0
…
Query (7f873814e200): is an invalid pointer
Connection ID (thread ID): 5810908
Status: NOT_KILLED

2

If mysql is shut down because of OOM. Then there will be such information in the system log:
Out of memory: Kill process 21451 (mysqld) score 169 or sacrifice child

You can check whether there is such information.

3

Many thanks for the reply. There are no such entries.

I thought I had seen that signal 11 was likely to be a memory problem.

The ‘apparmor’ message appears immediately before each crash. Should this give me any clues?