Andy Yates wrote:
You did this flushing and looking at the reference counts in a process that already had run for several days (and therefore was
quite
huge)?
It took about 24 hours.
Do you use C extensions that create non-Python objects (and therefore do not have reference counts and show up in the list)? Maybe, such a C extension is leaking.
No we do not use C extensions. In fact we can reproduce this behavior on a fresh install. On a fresh system create a python script that puts data in a session object.
s = context.REQUEST.SESSION t = ' ' * 1024 s['data'] = t print "foo" return printed
Then call this script with your favorite bench marking program. We used apache bench (ab). This will cause python2.3 to consume all available memory and crash or lockup. The speed at which this happens depends on the amount of data you assign to 't' and how fast you call the script. The session timeout does not seem to affect the memory use. We even tried setting the session timeout to 1 minute.
In a very basic sense this is all our production server does. When a user first comes to our site we query a mysql database for several hundred values. These values are then stored in the session object as a map. All other pages are built dynamically based on the values stored in the session object.
Is the session object system just not supposed to be used like this?
We need to do some back-of-the-envelope math here: Estimated bytes / entry: 16 Estimated entries / user: 150 Estimated overhead / user: 600 ================================ Estimated bytes / session: 3000 How many simultaneous sessions are we talking about? A few hundred simultaneous users could chew up RAM pretty fast. What is your "max number of sessions" value? Tres. -- =============================================================== Tres Seaver tseaver@zope.com Zope Corporation "Zope Dealers" http://www.zope.com