[Zope] Zope Lockup (ZPublisher stops responding?)

[Jean-Francois.Doyon@CCRS.NRCan.gc.ca]

Dieter,

Thanks for the update ...

My situation might be somewhat different though:

1) I don't use ZEO
2) This happens without me trying to "kill" anything, so basically, if
there's a "kill" signal being generated, it's not from me!
3) Which brings on the old problem of memory leakage ... I went through
EXTENSIVE reworking of my Zope setup, and it looks like the leak was gone
... Could it be it's really not? When I still had a noticeable memory
problem, sometimes the master thread/process would actually get a SIG11 or
SIG25 (If I remember correctly) and restart Zope properly.  Could it be I'm
actually STILL having a memory problem, only Zope no longer reacts nicely to
the signal?

I'm pretty sure my memory leak is gone honestly, the numbers do stabilize
after a day or so ... But the "lockup" problem occurs so much more often now
that I can't really tell!

Like I said, storage operations actually only happen internally to our
organization, so I'll try to track it down to see if there's a correlation
next time I see this happening.

Thanks for the help!
J.F.

-----Original Message-----
From: Dieter Maurer [mailto:dieter@handshake.de]
Sent: Friday, April 18, 2003 4:58 PM
To: Jean-Francois.Doyon@CCRS.NRCan.gc.ca
Cc: zope@zope.org
Subject: Re: [Zope] Zope Lockup (ZPublisher stops responding?)


Jean-Francois.Doyon@CCRS.NRCan.gc.ca wrote at 2003-4-17 14:09 -0400:
 > ....
 > The symptoms:
 > 
 > Zope stops responding to HTTP requests
 > Zope memory usage increases suddenly quite a bit
 > The number of apache processes increases quite a bit also
 > Can't kill Zope normally, need to do a -9 ...

We see this quite regularly but not yet often enough that
we could analyse it.

We understand the necessity to use "kill -9" to kill Zope.

  It indicates that Zope was performing a storage operation
  when the "kill" signal was received. In this
  case, the main thread (executing the "kill" signal handler)
  blocks on acquiring the storage lock. When the storage is
  a ZEO storage, deadlock occurs as the (now blocked) main thread is needed
  for ZEO communication.

There is a collector report with patch for it.


Dieter