PHP has several session settings that control the probability that garbage collection (i.e. deletion of expired sessions) will occur.
My question is: does this probability apply to all running Apache threads on all virtualhosts on any given Apache server?
- If the probability is set to 1/100, does that mean that any Apache thread that runs a PHP process goes into the pool of processes that may have gc run?
- or, does that apply only to the threads runnning for any given VirtualHost? Or other sort of partitioning?
- Finally, if a PHP process that triggers gc, does it perform gc on all PHP sessions? or just the sessions for that VirtualHost? Or other sort of partioning?
I'm trying to gauge wether I need to tune the gc_probability setting for a given VirtualHost, for the whole server, or what.