[Zope-dev] ZEO Client nonresponsive

Jan-Wijbrand Kolman jw@infrae.com
Thu, 10 Apr 2003 18:26:58 +0200


Hello,


I add up to two earlier postings where a nonresponsive, hanging or
seemmingly frozen ZEO client is described:

   http://mail.zope.org/pipermail/zope-dev/2003-March/019179.html

   http://mail.zope.org/pipermail/zope-dev/2003-February/018681.html

Esp. the later one is an accurate description of the situation we
experiece too:

   (..)All the zope processes were still running,
   CPU usage was low (almost nil for python),
   there was plenty of free physical memory & swap.
   Yet Zope was not responding to requests.
   A look at the access logs revealed that
   zope had not logged anything since the time
   we noticed the outage(..)

   (..)A restart seemed to fix everything, though one
   of the zeo servers went down again (same symptoms)
   about 20 minutes after starting. Restarted it again
   and both servers have been fine for hours now(..)

Using the "debugspinngingzope' howto did not help for me - I could not
get any usable information out of gdb.

I can add some details on my setup, which hopefully helps analysing
the problem.

Setup (all on Debian linux 2.4.18, Zope2.6.1, ZEO2.0.2, DBTab 1.1):

ZEO server, serving a FileStorage and a TemporaryStorage (to share
SESSION objects between the clients). I also tested a  setup where a
regular FileStorage was used.

2 ClientStorage nodes, using DBTab to mount the served FileStorage as
"/", and the TemporaryStorage as "/temp_folder". This nonresponsive
behaviour was also seen with just one ZEO client.

However, when this one node uses a default "temp_folder" as being
created at Zope startup (so not mounted from the ZEO server, but a
TemporaryFolder), I so far did *not* experience the nonresponsiveness.

If I need to provide more details which might help, please ask!


regards,
jw

-- 
Jan-Wijbrand Kolman
jw@infrae.com