[dev] slow pageload before authentication

[Michael Menge]

Hi,

and thanks Thomas

Quoting Thomas Jarosch <thomas.jarosch at intra2net.com>:

> Hi Michael,
>
> On 06/19/2015 03:32 PM, Michael Menge wrote:
>> after changing our production system to horde 5.2.5 (from horde 3)  
>> we discovered a strange
>> delay in loading the initial page (/ which redirects to login.php)  
>> Most of the time the page
>> loads in less than a second, but occasional it takes between 30 and  
>> 60 seconds.
>>
>> We discovered that the delay is on the server side, because the  
>> delay is visible in
>> the apache access logs. Setting the horde loglevel to debug we  
>> found for an delayed load of the initial
>> page the corrosponding pid produced over 32000 lines of
>>
>> HORDE [horde] Horde_HashTable_Predis: Retrieved keys  
>> (djmss6knc7qpr31c9batplpr31) [pid 31663 on line 233 of  
>> "/usr/share/pear/Horde/HashTable/Base.php"]
>>
>> for different keys. Is this number of keys expected behavior?
>> Any ideas what could cause this delay?
>
> two things I would try:
>
> - Run without any optimizer like APC or Predis.
>
>   This will involve a configuration change,
>   so back up conf.php first.
>

As we use a loadbalancer setup, we could not disable predis for sessions.


>   Do is still occur?
>
> - Install something like xdebug and try to get a call
>   trace that shows the excessive Horde_HashTable_Predis invocation.
>
>   Then we can go back in the call tree and see what's causing this.
>
>
> Reading your email again, it could also be some
> kind of garbage collection that's running every XX page calls.
> The xdebug trace might help.


I installed xdebug and created a profile for a long running process.
It is the garbage collection.  
Horde_SessionHandler_Storage_Hashtable->trackGC called
33.560 x Horde_SessionHandler_Storage_Hashtable->exists

Is there a way do disable Horde Session GC, and run the GC manually by cron?
Setting  session.gc_probability=0 in php.ini didn't help.




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