Symfony calls the PHP garbage collector on Ubuntu 14.04 even when session.gc_probability is set to 0

Question

As the title state for some reason my Symfony 2.5 Application is calling the php garbage collector even when all of my php.ini files have:

session.gc_probability = 0

Does anyone know how to prevent this from happening?

Error message im getting:

Notice: SessionHandler::gc(): ps_files_cleanup_dir: opendir(/var/lib/php5)
failed: Permission denied (13) in /<path-to-my-site>/var/cache/dev/classes.php line 432 

FROM PHPINFO():

Directive               Local Value   Master Value
session.gc_divisor      1000          1000
session.gc_maxlifetime  86400         86400
session.gc_probability  0             0

I know that i can just give the www-data user permission to the /var/lib/php5 folder or change the session.save_path to somewhere that the www-data user has access to already but i want to know why this process is even getting called when it should be disabled.

Answer 1

I found it, I guess the latest version of symfony is overwriting this by default when using the app_dev.php. The Symfony FrameworkBundle is setting the session.gc_probability = 1.

As of Symfony 3

However, some operating systems do their own session handling and set the session.gc_probability variable to 0 to stop PHP doing garbage collection. That's why Symfony now overwrites this value to 1.

If you wish to use the original value set in your php.ini, add the following configuration:

# config.yml
framework:
    session:
        gc_probability: null

https://symfony.com/doc/current/components/http_foundation/session_configuration.html#configuring-garbage-collection

Previous 2.x versions

To change this add the following to your config.yml

framework:
    session:
        gc_probability: 0

Then clear the dev cache

php app/console cache:clear

This is where it shows the gc_probability defaulted to 1. Why they dont just read from the php.ini settings im not sure.

http://symfony.com/doc/2.5/reference/configuration/framework.html#gc-probability

Answer 2

You can set path for sessions manually. See Symfony doc on sessions directory.

# app/config/config.yml
framework:
    session:
        handler_id: session.handler.native_file
        save_path: '%kernel.root_dir%/sessions'