This has just starting happening to one of our sites. While I can recreate a server crash by holding down the enter key on certain pages I am not certain this is the issue. When holding down the enter key and forcing a crash I can see the apache logs showing multiple posts. The kernel log shows the end result of a server crash and OOM starts picking off processes, as expected.
However, when the event happens in the wild, so to speak, there isn't anything unusual about the apache logs. The syslog show the details below suggesting
opac-main.pl is the culprit but I am struggling to find any form that posts to
opac-main.pl in order to cause multipl form submissions.
/var/log/syslog.1:Oct 1 11:49:26 srv1 kernel:
opac-main.pl invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0, oom_score_adj=0
/var/log/syslog.1:Oct 1 11:49:26 srv1 kernel: [<c10a3408>] oom_kill_process+0x68/0x220
/var/log/syslog.1:Oct 1 11:49:26 srv1 kernel: Out of memory: Kill process 6774 (mysqld) score 42 or sacrifice child
/var/log/syslog.1:Oct 1 11:49:26 srv1 kernel: Killed process 6774 (mysqld) total-vm:335720kB, anon-rss:183608kB, file-rss:0kB
/var/log/syslog.1:Oct 1 11:49:26 srv1 kernel: init: mysql main process (6774) killed by KILL signal