[ http://issues.apache.org/jira/browse/MODPYTHON-1?page=all ] Graham Dumpleton closed MODPYTHON-1: ------------------------------------
> Circular references starting from the request object create a memory leak > ------------------------------------------------------------------------- > > Key: MODPYTHON-1 > URL: http://issues.apache.org/jira/browse/MODPYTHON-1 > Project: mod_python > Type: Bug > Versions: 3.1.3, 2.7.10 > Reporter: Nicolas Lehuen > Assignee: Nicolas Lehuen > Fix For: 3.2.7 > Attachments: garbage_collection.patch, requestobject.c.gz > > Hi, > I'm running Apache 2.0.50, mod_python 3.1.3 with Python 2.3.4 on Windows XP > Pro and Windows 2000 server. > I finally found a source for the memory leaks I have been observing for a > while now : if you store an object in the request object that reference > directly or indirectly the request object itself, it builds a circular > reference. This circular reference does not seem to be garbage collected. > The test handler : > from mod_python import apache > def handler(req): > # req.foobar=req > req.content_type='text/html' > req.write('OK') > return apache.OK > I used Apache Benchmark : > ab -c 5 -n 100000 http://localhost/test.py > With the comment line, everything is OK, I do not see any memory leak. > If I uncomment the 'req.foobar=req' line, the memory leak shows up. My Apache > process normally uses around 20 MB without the comment, and in 30 seconds of > running the above handler (comment removed) with the above Apache Benchmark > command, it reaches 125 MB ! > Normally, circular reference are collected by the garbage collector of > Python, but unfortunately when defining object from C, you have to do a few > tricks to support this : > http://www.python.org/doc/2.3.4/api/supporting-cycle-detection.html > It seems that this is not done in mod_python, by having a look at > requestobject.c. > I find this quite a big problem, and I don't find any workaround except > "Don't reference the request object from anywhere that might be referenced by > the request object", which is a pretty big limitation, quite annoying in the > application I'm building. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
