Fatal error: Allowed memory size of 33554432 bytes exhausted

#1
I'm running Litespeed 2-CPU Enterprise edition (v3.3.11) on Linux x86 4GB RAM (web server only) and my users are reporting the following error on my forums:

Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 16783 bytes) in /path/to/mysite/forum/showthread.php on line 1265

Is it a case of adjusting memory_limit in php.ini or is there a setting within the Litespeed admin that I can amend? Also, what would be the suggested memory limit for a site that has around 2800 users online peak, 2200 average (15 min timeout).

Your help would be appreciated.
 
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