Issue Troubleshooting high memory usage of Apache & PHP-FPM

[elbobo]

Server operating system version

Debian 11.9

Plesk version and microupdate number

Plesk Obsidian v18.0.57_build1800231218.09 os_Debian 11.0

Hello!

I have Plesk Obsidian 18.0.57 Web Pro Edition installed on a VM with 8 GB of RAM and I am currently hosting 26 domains. During the last month I am having outages because of high memory utilization from Apache and PHP-FPM according to Plesk's messages and sometimes even the server reboots.

How can I go about to find the root cause?
What I would like to do is first get statistics of every domains consumption for a small period of time, then find how much the total memory consumption from all domains as a percentage of the whole memory and then perhaps start to limit memory consumption for specific domains.

 

[pleskpanel]

Are you able to SSH or login to Plesk while the incidents are occurring or is this an "after hours" type of scenario each time?

 

[elbobo]

Are you able to SSH or login to Plesk while the incidents are occurring or is this an "after hours" type of scenario each time?

Typically I am notified by emails Plesk sends after the fact and I have SSH access.

 

[andreios]

Have you tried to upgrade Plesk? You cloud also try to upgrade the OS but first you have to update to the latest Plesk version

plesk installer upgrade plesk stable

https://support.plesk.com/hc/en-us/...-upgrade-procedure-on-Linux-server-with-Plesk
In case this related to an high amount of traffic, have you tried to use nginx caching?
You could watch your logs or use "btop" to see whats going on.

tail -f /var/www/vhosts/*/logs/*log

Maybe you want to try a dedicated PHP handler, you could isolate the process better.

https://support.plesk.com/hc/en-us/articles/12377820871447-How-to-apply-new-PHP-handler-to-multiple-domains-via-CLI-in-Plesk-for-Linux