[Skunkworks] how to get more than one instance of a threadPool class in a single twisted reactor

10 Nov 2011


      I have been looking for a way to run different processes in a single
reactor  without having to share the threadpool class and this is what i
have come up with. Twisted fans, lemi know if you have another way of doing
it.

much of the code have been pulled from the reactor base.py

from twisted.internet import reactor,threadsfrom time import sleep

class Thread:
    def __init__(self,name="threadpool1"):
        self.name=name
        self.threadpool = None


    def _initThreadPool(self):
            """            Create the threadpool accessible with
callFromThread.            """
            from twisted.python import threadpool
            self.threadpool = threadpool.ThreadPool(
                0, 10, self.name)
            self._threadpoolStartupID = reactor.callWhenRunning(
                self.threadpool.start)
            self.threadpoolShutdownID = reactor.addSystemEventTrigger(
                'during', 'shutdown', self._stopThreadPool)
    def _stopThreadPool(self):
            """            Stop the reactor threadpool.  This method
is only valid if there            is currently a threadpool (created
by L{_initThreadPool}).  It            is not intended to be called
directly; instead, it will be            called by a shutdown trigger
created in L{_initThreadPool}.            """
            triggers = [self._threadpoolStartupID, self.threadpoolShutdownID]
            for trigger in filter(None, triggers):
                try:
                    reactor.removeSystemEventTrigger(trigger)
                except ValueError:
                    pass
            self._threadpoolStartupID = None
            self.threadpoolShutdownID = None
            self.threadpool.stop()
            self.threadpool = None
    def getThreadPool(self):
            """            See
L{twisted.internet.interfaces.IReactorThreads.getThreadPool}.
  """
            if self.threadpool is None:
                self._initThreadPool()
            return self.threadpoolclass Server:
    def __init__(self):
        pass
    def request(self,params):
        sleep(0.5)
        print "Server: ",paramsclass Expiry:
    def __init__(self):
        pass
    def request(self,params):
        sleep(0.5)
        print "Renewal: ",params
if __name__=="__main__":
    ##########################
    ##### first threadpool ###
    ##########################
    t1=Thread('t1')
    mainPool=t1.getThreadPool()
    mainPool.adjustPoolsize(maxthreads=2)

    #############################
    ##### second threadpool #####
    #############################
    t2=Thread('t2')
    expiryPool=t2.getThreadPool()
    expiryPool.adjustPoolsize(maxthreads=10)

    print mainPool.max,mainPool.name
    print expiryPool.max,expiryPool.name

    for i in range(0,10):
        d=threads.deferToThreadPool(reactor, mainPool,Server().request,{"id":i})

    for k in range(0,10):
        d=threads.deferToThreadPool(reactor,
expiryPool,Expiry().request,{"id":k})

    reactor.run()

[Skunkworks] how to get more than one instance of a threadPool class in a single twisted reactor

gisho