Httpd processes spiking

Hey guys!

So I have a Grafana Server 6.4 (upgrade soon to be done) installed in the same server as my Zabbix Server.

The server itself is a 2 vCpu machine with 4GB of RAM, which works fine.

Last weekend something weird happened. The httpd processes on the server spiked up , processor load went to 70 and froze everything. During the troubleshooting I found no apparent error messages on the zabbix, grafana and apache logs. However, when I stopped the Grafana Server process, the situation went back to normal. After that, only a reboot solved the issue.
This weekend it happened again, at around the same time (21:45).

Does any one have any ideas as to why this happens or where to troubleshoot this from?

Thanks a lot fellows!