How can I check what my server was doing at midnight, to locate the high memory spike, which he is still holding on.

Only things I'm running on the server is Apache2 with a Flask app, and a Tomcat7 server for some Java services, both are doing nothing.

Is there any system logs or something that can tell me whats going on?

New relic server stats:

[![New relic server stats](https://i.stack.imgur.com/Ud40r.jpg)](https://i.stack.imgur.com/Ud40r.jpg)

Glances stats:

[![Glances stats](https://i.stack.imgur.com/QaQi8.jpg)](https://i.stack.imgur.com/QaQi8.jpg)