[ZODB-Dev] Zope or Zeo hanging up sockets

Toby Dickenson tdickenson@geminidataloggers.com
Wed, 28 Nov 2001 09:47:38 +0000


On Wed, 28 Nov 2001 16:44:21 +1300, "Matt" <matt@virtualspectator.com>
wrote:

>First of all, and don't laugh, the following are the external methods
>involved :

There may be an obvious soution... Does that external method use any
extension modules that might not be giving up the python global lock,
or any python modules that are using thread synchronisation?

(my appologies if that question is *too* obvious)

>dom document of the 4Suite kind

I remember one of Python's xml libraries relies on the python garbage
colelctor to break circular references. Is that 4Suite, or another
one? The blockage may be due to the garbage collector, although 40s is
much slower that I have ever seen it before.


>>>A sockstat shows that
>> connections
>> > are piling up to Zope.  I watched the logs for a while and found
>> that when a
>> > certain external method was called that takes up to 10 seconds to
>> run and
>> > return, that all the other requests pile up behind it.  When it
>> finally goes
>> > through then a burst of some, but not all, of other pending requests
>> goes
>> > through

You could modify your external method to write a log file with
timestamps on entry, exit, and at any landmarks within the external
method. That may help isolate exactly what is blocking.



Toby Dickenson
tdickenson@geminidataloggers.com