Failed calling MemcachedSessionModule::gc()

[OskHa]

It seams that the garbage collection is not working.

/hhvm/php.ini

session.save_handler = memcached
session.save_path = "xx.xx.xx:11211"
session.gc_maxlifetime = 1209600
session.gc_probability = 1
session.gc_divisor = 10000

;memcached.sess_locking = on
;memcached.sess_lock_wait = 150000
memcached.sess_prefix = "xxx."

[daniele-rapagnani]

I'll second this one, we are experiencing this problems on our servers too.
We tried to investigate the issue to no avail.

[etcook]

+1

[dng-dev]

+1

[jeroneemou]

+1
having the same issue, HHVM 3.5

[therealssj]

+1 same issue here 3.6.3

[jwatzman]

PHP is refcounted... I assume the "GC" referred to in these options is the cycle collector? If so, HHVM does not implement a cycle collector. There are some experiments on changes to its memory management strategy that might get a cycle collector as part of that, but they're still super experimental and might not pan out at all.

Can you elaborate on what the exact problem is that you're seeing? It's not like we leak everything, refcounting ensures that most data get collected. Does MemcachedSessionModule create a lot of cyclic references?

[paulbiss]

I'm not entirely sure what gc() is supposed to do on this class but it looks unimplemented.

hhvm/hphp/runtime/ext/memcache/ext_memcache.php

Lines 755 to 757 in 8911447

	public function gc($maxLifetime) {
	return true;
	}

[jwatzman]

Ah, I was fixated on these INI options

session.gc_maxlifetime = 1209600
session.gc_probability = 1
session.gc_divisor = 10000

which I think are unrelated to the original report?

[jeroneemou]

This is my exact use case:

[nikic]

@jwatzman Those ini options are for controlling the GC of sessions only (unrelated to the normal value CC). They specify how often (gc_probability/gc_divisor) the session GC collects sessions that have exceeded gc_maxlifetime.

[kenliao94]

+1

[basselalaraaj]

+1

[cosmok]

+1