[Zope-dev] RE: [Zope] Re: Zope hanging (poss. threads-related)

Amos Latteier Amos@digicool.com
Thu, 13 Apr 2000 14:53:01 -0400


> > I'm actually wondering if reducing that zombie_timeout (and
> > maintenance_interval in medusa/http_server.py) would go 
> anywhere towards
> > alleviating this problem as a temporary measure. Would 
> there be any reasons
> > not to try this?

The ZServer zombie stuff is to get rid of zombie client connections, not
zombie publishing threads. These are quite different beasts.


> > Everything before the call to handle() is 100%. Sometimes, 
> however, we don't
> > get from handle() to the next stage. This is on Zope 2.1.6, 
> which I've been
> > running with up to 100 threads, although I unfortunately 
> can't excercise
> > that many! 

In general there is little reason to have so many publishing threads.
You almost never need that many unless you have a bunch of requests that
can take a *long* time.

If, on the other hand, you are trying to provoke some kind of thread
contention issue I advise you to publish resources that take a long time
to return. That way you can easily pile up as many publishing theads as
you want to.

> > I've added this logging to the Zope 2.1.3 serving the live 
> site, and will
> > report my findings as soon as something untoward occurs. 
> Maybe others who
> > are experiencing hanging would also be able to do some 
> extra logging and
> > report the results [now, there, I see Wiki would be really useful!].
> > 
> > In the meantime, any suggestions as to where to go next 
> will be keenly acted
> > on!

In my experience when a Zope publishing thread hangs its almost always a
problem with the published resource. Maybe there's something that puts
Zope in a loop that never exits, or maybe there's some DA weirdness that
hangs the thead.

My advice is to try and identify which requests hang using debug logging
and examine the resources that those requests use.

-Amos

--
Amos Latteier         mailto:amos@digicool.com
Digital Creations     http://www.digicool.com