VPS reboot automatically 3am every day

The problem started about a week ago where I notice I would notice a VPS requires your attention Email from the bot every morning at 3:11AM Pacific Time. I shoot several tickets to the support and I got back canned messages about increasing VPS memory usage.

There are no cron jobs whatsoever. No abnormal activities going on around 3am from what I gather from the access log and error log. I am using Lighttpd + PHP 5.2 FastCGI + XCache. My VPS has a relatively small memory footprint at 120MB (excluding cache)

I think what caused the reboot is a sudden spike that lasts a few seconds around 3:11AM that causes the reboot robot to kill my VPS. Is my only option PsManager? Is there any other way to narrow down what’s going on around that time?[hr]
Support has helped me pin down the problem. Thank you so much! The culprit was the statistics analysis processes that run every morning at 3…