Question Opcache & PHP-FPM Questions

[Dec@de42]

Hello everyone,
I am currently trying to understand 2 things in Plesk, or web hosting in general:
Opcache in combination with
PHP-FPM and PHP-FPM Dedicated

(I know there are handlers for PHP-FPM Apache and nginx, but this is not relevant for my question, I guess)

I already found some threads about those topics here at the Plesk forum, like this one and this linked guide, but they are confusing me even more.

So, here is what I found out so far (or what, I believe, is correct. Please correct me if I'm wrong)

1. PHP-FPM and Dedicated use the same technology, and FPM is currently recommended because it is a more advanced Fast-CGI handler (here)
2. PHP-FPM Dedicated is more stable & faster because it spawns its process, but also needs slightly more resource than non-dedicated FPM
3. Opcache values specified in the "Additional configuration directives" for Plans/Subscriptions using PHP-FPM dedicated should work because they are using their own PHP-Handler and therefore have a dedicated opcache memory:

If my assumptions above are correct, then my questions are:

• How do I specify the opcache memory size for the non-dedicated PHP-FPM handlers? Is this php.ini or this 10-opcache file the correct one?
• Are the non-dedicated ones sharing/using the same opcache memory pool?
  • If yes: Is there any way to make sure every non-dedicated PHP-FPM subscription is getting its chunk of memory, i.e. by specifying a memory limit in the Additional configuration directives?

Thanks in advance for your help!

 

[safemoon]

following this

 

[homberger]

bump

 

[Kaspar]

Seems your topic got missed.

If my assumptions above are correct, then my questions are:

• How do I specify the opcache memory size for the non-dedicated PHP-FPM handlers? Is this php.ini or this 10-opcache file the correct one?

In the php.ini of the corresponding PHP version you can adjust the opcache.memory_consumption value.

• Are the non-dedicated ones sharing/using the same opcache memory pool?
  • If yes: Is there any way to make sure every non-dedicated PHP-FPM subscription is getting its chunk of memory, i.e. by specifying a memory limit in the Additional configuration directives?

Yes all non-dedicated PHP versions share the opcache memory pool. Thats why the opcache_get_status PHP function is disabled by default. Otherwise different users/customers can view each others opcache objects. There is however no way to distribute opcache memory between users.

 

[Cike76]

You can tune it in the corresponding version of 10-opcache.ini ( globally for the sites using that version of PHP )

In those files yon can find the corresponding settings ( most of them commented out )