[imp] process / memory problems in new release (?)

[Matthew Dunham]

>>>> I've confirmed that these problems don't exist in Horde 3.2.1/IMP 4.2,
>>>> so the trigger is clearly something that's been introduced in the past
>>>> months' development efforts. Just for fun I disabled caching, 
>>>> thinking this new feature might be the culprit -- but no dice.
>>>
>>> Which caching feature did you disable? There are a number of 
>>> different ones; several are called out in the accompanying comments 
>>> as ones that increase session size, which might lead to memory growth 
>>> in httpd processes.
>>
>> ah, the new horde object caching system (if that's what you call it).
>>
>> $conf['cache']['driver'] = 'file';
>>
>> i'm using this setting in production, but see the same behavior with:
>>
>> $conf['cache']['driver'] = 'none';
> 
> That will definitely not hurt you and may hurt. You should look through 
> the IMP settings for things that might increase session size - I don't 
> have them in front of me right now, sorry.

So I'm not sure what this first sentence means.

My tests seem to indicate that setting this cache driver to 'none' 
doesn't change the symptom -- process size increases with either of 
these settings.

I would assume that file-based cache is storing objects in the 
filesystem rather than memory. Is this not correct?

Also, when you suggest IMP settings may increase session size, do you 
suggest the session object is being cached in memory regardless of the 
cache driver setting?

-m