[Zope] Zeo Client hanging

[Allen Schmidt Sr.]

I see references to asyncore.py near the end of the thread listing when 
using DeadLockDebugger and seeing a stuck thread process. The tread 
eventually clears out but sometimes an impatient user reloads, reloads, 
reloads...and then all 4 threads are stuck on exact same thing. Then you 
can see the same URL jump to the other Zope/ZEO client and same thing 
happens there. Another few reloads and one user has effectively crashed 
the site....until the threads clear themselves out. Usually is a catalog 
search for a news article or something spanning our 6 years of online 
news articles searching on the word 'bob' or something like that.

+1 for DeadlockDebugger... love it.

Allen




Paul Winkler wrote:

> On Wed, Oct 18, 2006 at 07:32:38AM +0200, Maciej Wisniowski wrote:
> 
>>>zope 2.8.5 + zeo
>>>python 2.3.4 (red hat distribution)
>>>Red Hat RHEL 4
>>>Plone 2.1.2
>>>
>>>Our zeo clients hang intermittently.  We have no way of reproducing the
>>>problem, but it occurs daily.  The client hangs and a restart seems to 
>>>fix the
>>>problem.
>>
>>Install DeadlockDebugger and you'll be able to see what is
>>the state of your threads when Zope becomes unresponsive.
>>
>>
>>>In the event log with tracing on we get
>>>
>>>Trace zeo.zrpc.Connection(C) wait(16697) {server:8100} pending, async=0
>>>
>>>There are hundreds to thousands of these until the server is restarted.
>>>
>>>In the zeo log we get
>>>
>>>Error caught in asyncore asyncore.py
>>>
>>>error:(110,'Connection timed out')
>>
>>I'm not sure what these errors are. Maybe firewall between zeo
>>server and zeo client closes the connections or something like that?
> 
> 
> That was my guess too.
> See this thread:
> http://aspn.activestate.com/ASPN/Mail/Message/zope-list/2916870
>