Optimizing cPanel accounts: dealing with php-fpm resource limits?

hey everyone, running into some persistent challenges managing a shared cPanel/WHM server here. we host quite a few client sites, and lately, i've been seeing intermittent performance dips that are really starting to bug me.

the core issue seems to be specific high-traffic accounts hitting php-fpm resource limits. this manifests as 50x errors for those sites and a general slowdown across the server, which is clearly not ideal for client satisfaction. i'm pretty sure it's tied to pm.max_children and request_terminate_timeout settings, but tweaking them feels like a constant balancing act.

i've already tried adjusting various php-fpm pool settings through WHM's MultiPHP Manager, even dropping .user.ini files for specific problematic accounts. i've also gone through apache error logs and LFD logs, and they consistently point to the same thing.

here's a snippet from /var/log/php-fpm/error.log that keeps popping up:

[04-May-2024 10:35:12] WARNING: [pool domain.com] server reached pm.max_children setting (5), consider raising it
[04-May-2024 10:35:13] WARNING: [pool domain.com] child 12345 exited on signal 9 (SIGKILL) after 120.000 seconds from start
[04-May-2024 10:35:13] NOTICE: [pool domain.com] child 12346 started
[04-May-2024 10:35:15] WARNING: [pool anotherdomain.net] server reached pm.max_children setting (5), consider raising it

so, i'm looking for some advanced strategies or maybe less obvious WHM configurations to intelligently manage php-fpm resource limits per account. the goal is to ensure stability without constantly over-provisioning resources or getting stuck in a loop of manual tweaks. anyone have some deep insights into optimizing this specific php-fpm configuration in a cPanel environment?