[horde] large session entries in horde_sessionhandler

[liam hoekenga]

If this is a more appropriate conversation for the IMP list, let me know, and
I'll move it.

>> No.  By default, IMP *doesn't* store the body contents in the session
>> for the very reason it has the possibility of creating extremely large
>> sessions.  This new config item is designed for those of us running IMP
>> on small systems with minimal users to take advantage of caching the
>> bodytext also.

I have noticed some strange behavior...

On our production servers, as soon as I log in to Horde, my entry in 
the session
table includes about 23k of text in session_data.

On our development servers, the same action generates a much smaller
session_data (it only contains an array for hordeMessageStacks).

Same software, same hardware, only difference is the amount of load the 
machine
sees.  Does horde cache more when it's heavily loaded?  Is there a way 
to limit
the amount of information it caches in the session?

Michael suggests that IMP doesn't store body contents in the session, 
but we've
seen otherwise.  Our sessions contain messages - although I don't know if
they're the last message read, or the message currently being read, if these
messages contain attachments, the session data can grow quite large.  I don't
think it's reasonable to suggest that the way to fix that is to limit the size
of the messages our users receive.

Is the cache system at all related to this?  We've currently got it set 
to cache
objects in the filesystem, in a location determined by Horde::getTempDir(). I
don't really see anything in /tmp or /var/tmp.. could this stuff be getting
stuffed in the session?

Liam