Mailman 3 September 2009 - Twisted

Re: [Twisted-Python] I found an interisting comment about Twisted vs. Erlang
by Michael Handverger Sept. 30, 2009

Sept. 30, 2009

> The biggest advantage of Twisted is a shorter development time, and the > availability of Python libraries. But I wonder if running something of the > scale of Facebook chat would be feasible at all, or if there are people on > this list that have run many parallelized twisted servers that saturated > many multi-core machines? In other words, are there practical examples of > large-scale Twisted deployment? My previous employer isn't quite up to Facebook's size, but they … [View More]

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Re: [Twisted-Python] Not understanding buildProtocol(), any clarification?
by exarkun＠twistedmatrix.com Sept. 30, 2009

Sept. 30, 2009

On 08:16 pm, cyclops(a)speakeasy.net wrote: >Hello, I'm trying to understand and use buildProtocol(), which isn't >working as I expected, in two ways :) Question 1. If I have, on the >Server side: > >class MyFactory(Factory): > protocol = MyTestProtocol > def buildProtocol(self, addr): > p = Factory.buildProtocol(self, addr) > p.transport.write('connected.\n') > return p > >Should this work? … [View More]

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[Twisted-Python] Not understanding buildProtocol(), any clarification?
by John Crawford Sept. 30, 2009

Sept. 30, 2009

Hello, I'm trying to understand and use buildProtocol(), which isn't working as I expected, in two ways :) Question 1. If I have, on the Server side: class MyFactory(Factory): protocol = MyTestProtocol def buildProtocol(self, addr): p = Factory.buildProtocol(self, addr) p.transport.write('connected.\n') return p Should this work? Would the write() function execute? I thought that 'p' was a fully usable Protocol object at … [View More]

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[Twisted-Python] strange exception on Python 2.6 + Snow Leopard
by Phil Christensen Sept. 30, 2009

Sept. 30, 2009

hey all, I just upgraded to Mac OS X 10.6 which includes Python 2.6.1. I'm running the latest SVN HEAD of Twisted, but when I run twistd I get an exception before it continues working (apparently) normally. Here's what I'm seeing: thrawn:~ phil$ twistd Traceback (most recent call last): File "/Users/phil/Workspace/Twisted/twisted/python/usage.py", line 413, in __str__ return self.getSynopsis() + '\n' + self.getUsage(width=None) File "/Users/phil/Workspace/Twisted/twisted/… [View More]

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[Twisted-Python] AlreadyCalledError trying more than a server
by Antonio Beamud Montero Sept. 30, 2009

Sept. 30, 2009

Hi all: I've implemented my client as comes in twisted documentation (FingerProxy example). I want to connect with several machines at the same time, send and receive data from this servers and start again (monitoring in one word). I've created a ClientFactory and a loop like this: conf['hosts'] = [list of hostnames] commands = [list of string commands, like 'status' or 'temp'] def runall(data): nodes = [] for h in conf['hosts']: mcf = manager.… [View More]

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[Twisted-Python] I found an interisting comment about Twisted vs. Erlang
by Alec Matusis Sept. 29, 2009

Sept. 29, 2009

PS. >From my experience, the hardest problem in running large-scale Twisted servers is finding memory leaks, and to a lesser extent debugging intermittent silent server crashes. It's not easy to attach a debugger to a production sever if you are looking for sources of intermittent crashes for example. Looking for memory leaks, esp Python garbage collection problems/circular references is not easy as well, the manhole does not always help here. Again, attaching a debugger that allows to … [View More]list *all* objects in the memory, is not often feasible for a production server under high load. And memory leaks often appear only under CPU utilization, due to problems with scheduling garbage collection. I believe E has a way to dynamically and meaningfully inspect ALL objects in the memory of any running process. > I think we are accounting way too much time to the unfounded > unaccountable random blathering of a troll :-) As you can see from the %CPU column, I have my reasons for concern ;) This is current copy and paste from a node with 2x quad core xeon L5420 @ 2.50GHz - 1 twistd process per core. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 24448 nobody 20 0 991m 607m 2452 R 99 4.3 24764:37 twistd 28553 nobody 20 0 909m 453m 2412 R 95 3.2 1346:51 twistd 24640 nobody 20 0 1092m 676m 2452 R 93 4.8 32750:14 twistd 29900 nobody 20 0 802m 362m 2412 R 93 2.6 1180:53 twistd 24279 nobody 20 0 761m 277m 2424 R 42 2.0 13891:58 twistd 32422 nobody 20 0 1381m 962m 2372 R 10 6.9 13241:54 twistd 24210 nobody 20 0 599m 236m 2396 S 4 1.7 9063:29 twistd 29862 nobody 20 0 323m 14m 2384 S 2 0.1 71:53.50 twistd > -----Original Message----- > From: twisted-python-bounces(a)twistedmatrix.com [mailto:twisted-python- > bounces(a)twistedmatrix.com] On Behalf Of Laurens Van Houtven > Sent: Tuesday, September 29, 2009 12:28 PM > To: Twisted general discussion > Subject: Re: [Twisted-Python] I found an interisting comment about > Twisted vs. Erlang > > I think we are accounting way too much time to the unfounded > unaccountable random blathering of a troll :-) > > _______________________________________________ > Twisted-Python mailing list > Twisted-Python(a)twistedmatrix.com > http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python _______________________________________________ Twisted-Python mailing list Twisted-Python(a)twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python [View Less]

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[Twisted-Python] reactor blocked
by Jacopo Pecci Sept. 28, 2009

Sept. 28, 2009

How could I get the first result as soon as ready and therefore parallelize things? I don’t want to block the reactor with further processing if It has some results ready to be redurned. thanks, Jacopo SERVER: fibo=Fibonacci() fact=pb.PBServerFactory(fibo) reactor.listenTCP(port, fact) reactor.run() CLIENT: fact=pb.PBClientFactory() reactor.connectTCP(host, port, fact) d=fact.getRootObject() n1=10000 d.addCallback(lambda obj: obj.callRemote("compute1", n1)) d.addCallback(elaborateResult1) … [View More]

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[Twisted-Python] PostgreSQL LISTEN NOTIFY example?
by Steve Sept. 28, 2009

Sept. 28, 2009

My first message was sent as an HTML attachment - sorry! Hello, this is my first post to this list. I only started exploring Twisted less than a week ago. One thing that I would like to do is trigger a function via the PostgreSQL NOTIFY mechanism. Does anyone have an example or link to an example of how to correctly do this? I have something working but I am not sure if it is the best way.I would post the code but I am at work right now.

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[Twisted-Python] PostgreSQL LISTEN NOTIFY Example?
by Steve Sept. 28, 2009

Sept. 28, 2009

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[Twisted-Python] Having touble with spread.pb un-serializing an object
by Benjamin Ash Sept. 28, 2009

Sept. 28, 2009

Hi, I am trying to send new style classes that implement __slots__ with spread.pb. Things seem to go awry when attempting to un-serialize the objects on the client side. I am not sure if this is a known issue. How can I work around this issue? Thanks, -ben Stack trace: """ Unhandled error in Deferred: Traceback (most recent call last): File "/usr/lib/python-2.6/lib/python2.6/site-packages/twisted/spread/pb.py", line 514, in expressionReceived method(*sexp[1:]) File "/usr/lib/… [View More]

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