I don't know when but it's within 12 hours today, lsphp suddenly stopped working and configurations were reset back to the default config. lsphp5 Run on Startup went back to 'No' from SuEXEC Daemon A lot of abort error code 4 on logs Affected sites mostly Wordpress blogs I just restarted the server and everything seems to be fine for now. I have a working zend opcache with 1.5gb allocated memory. Just to be safe, I doubled lsphp5's soft and hard memory limits before I restarted the server (LSWS restart). --- update --- stderror log: 2014-05-16 09:43:52.467 [STDERR] Fri May 16 09:43:52 2014 (545034): Fatal Error Unable to allocate shared memory segment of 1610612736 bytes: mmap: Cannot allocate memory (12) I guess this was caused by the opcache. Should I increase opcache's memory from 1.5gb to 3gb? Should lsphp5's memory limits be always bigger than the opcache's?