A combined reply ...
>Anyway, your problem may have nothing to do with the details of your
>application if something like this is happening, so you should verify
>that you can successfully connect at all.
Good advice, and yes, we did confirm the connection upfront in a simple
we test the connection, storing and retrieving from the ZODB with ZEO
The client and server run on different machines. (XP and linux respectively)
> > As long as you ensure that the "asyncore" mainloop is running, there
>> should not be a problem to have more "asyncore" clients.
>> If you happen to run your application on Linux (and use the "GDB"), I
>> can provide detailed instructions on how to find out where your code
>That would be helpful!
As said above, the client runs on Windows XP, the server on Linux (debian).
>asyncore gives me a headache.
> I wonder whether this could be the problem:
>Paul said he's calling ZEO "from within the proxy code", but it sounds like
>the proxy code itself runs "as a side effect" of asyncore callbacks. If the
>flow is like this:
> asyncore mainloop invokes POP3 proxy code
> POP3 proxy code makes a synchronous ZEO call
I think that's exactly how the Proxy runs, we use asynchat and the
to trigger a callback, so it appears the code runs 'magically' at first glance.
>then I figure the app may well hang then: the thread running the asyncore
>mainloop is still running a POP3 proxy callback, waiting for a response that
>can never happen until the asyncore mainloop gets control back (in order to
>send & receive ZEO messages).
>IOW, if Paul added print statements to ZODB's ZEO/zrpc/smac.py's
>SizedMessageAsyncConnection readable() and writable() methods, I bet they
>never trigger when the app appears to be hung (which would mean that the
>thread running asyncore's mainloop is in fact not getting a chance to run
>the asyncore loop anymore).
You're right - I added the suggested comments as first line in the readable()
and writable() methods
they never appear.
Could I do synchronous calls to the ZEO server?
An other option to bypass the problem is to use Zope/XMLRPC to do what we want,
I assume that will not suffer they same problem.
Your opinion would be much appreciated,
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