[TYPO3-dev] cache framework - exception in apc backend when no space is left

[Dominique Feyer]

I think using opcode cache to cache user data is not a good idea, switch
to memcache or an other dedicated caching system for user data.

Andreas Kiessling wrote:
> Hi,
> 
> today i tried to use the cache framework with apc, but was faced with a
> "for me" not understandable exception, that the value could not be set,
> since the opcode cache did work fine and also the server was just idling
> with no signs of errors.
> 
> AFAIK apc adresses by default 32MB, and after some reading, i realized
> that this is surely not enough to use it with TYPO3 ;)
> We had already upped it to 62MB, but even that was filled up by the
> opcode cache and so there was just no space for any user cache entries.
> When the cache backend tried to write to apc, the apc_store function
> simply returned false. That event may hit you unprepared, probably just
> add an extension that includes a big framework or add some installations
> to your server.
> 
> We upped the setting to a limit that we will hopefully never hit, but
> probably the framework should "degrade" in such a case? apc does not
> return a special message if there is not enough space and this is for
> sure some "advanced" option, but the current situation does not really
> make me happy.
> 
> Any suggestions on how to proceed? Drop apc and go for memcache? Make
> the apc backend "degradable"?
> 
> Regards,
> Andreas