Hi there
A few versions back FPM was introduced and we blindly activated the feature, as usually whm/cpanel works fine out of the box.
This feature however reacts unexpected in a shared hosting setup.
It seems FPM is meant to run one site (one user). So if we use Cpanel (out of the box) for multiple sites, every client (every site) gets it's own pool and if we activate FPM with max_children=20 , every client can expand to 20 processes. If they in a rare case all do so at the same time, the server will run out of memory (and oom kicks in).
The Internet suggests that I should experiment, give some sites like 5 processes, others 2 or put some on "pm=demand" ( not dynamic ) and look at the logs for "you should increase number of childs" to further tune the setup... Is that really the only way?
I found a hint to something like max.processes. This would globally cap the max processes ALL Pools combined. But I can't figure out where to put it. Every configfile is telling me that I should use the "interface".
I could also make all sites run as one user, but I don't think cpanel will support that.
If you know what I can do?
Edit: toned it down a bit
A few versions back FPM was introduced and we blindly activated the feature, as usually whm/cpanel works fine out of the box.
This feature however reacts unexpected in a shared hosting setup.
It seems FPM is meant to run one site (one user). So if we use Cpanel (out of the box) for multiple sites, every client (every site) gets it's own pool and if we activate FPM with max_children=20 , every client can expand to 20 processes. If they in a rare case all do so at the same time, the server will run out of memory (and oom kicks in).
The Internet suggests that I should experiment, give some sites like 5 processes, others 2 or put some on "pm=demand" ( not dynamic ) and look at the logs for "you should increase number of childs" to further tune the setup... Is that really the only way?
I found a hint to something like max.processes. This would globally cap the max processes ALL Pools combined. But I can't figure out where to put it. Every configfile is telling me that I should use the "interface".
I could also make all sites run as one user, but I don't think cpanel will support that.
If you know what I can do?
Edit: toned it down a bit
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