[Zope] System performance threads/proccesses & random crashes (SIGPIPE)

[Zahid Malik]

I had similar problem with zope 2.5.0 and 2.5.1b1 crashing all the time
it was a real pain and really embarrassing (luckily still beta
testing).

After experimenting around we narrowed it down to the fact the crashes
seemed to happen when two of us tried to write (possibly) to the
postgres database (using ZPoPy 2.0.8). We could more or less make it
happen at will doing with two people on at the same time.

My solution: in z2.py set  NUMBER_OF_THREADS=1 instead of 4 (default).
This fixed it completely never had a crash since. Performance doen't
seem affected either although haven't really stress tested performance
(we did stress test for crashing and it was fine).

My guess is that the problem is in ZPoPy although I'm not sure. When I
get the chance I will do a more thorough check and send it to the
collector.

Good luck and let us know how it  goes. I must admit I really hoped that
going to 2.5.1b1 would solve the crashing problems, the whole thing
seriously made me think twice about zope in a production environment.


Zahid


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