multithreading - Python Multiprocessing Processes seem to share objects also the should -

in multiprocessing code several workers parallel processing.

the workers should communicating through request_queue , shared value lock.

but seems right because of "forking" when starting e.g. worker #4 , #5 share same dictionary document. found out using id(document) see memory address.

due storing document in mongodb, driver writting _id document, strange errors appear.

it has ensured every worker completly isolated expected queue , shared value, , don't know how right now.

the workers started with:

for in range(workers):     worker( request_queue,i,val, lock ).start()  class worker(process):  def __init__(self, queue,ident,val,lock):     super(worker, self).__init__()      self.queue= queue     self.idstr= str(ident)     self.val = val     self.lock = lock     dbconn = dbconnector.dbconnector()     self.mongoconnection = dbconn.getmongoconnection()     self.flagcontroller = flagcontroller()     print "ident" + self.idstr   def run(self):     print 'worker started'     # initialization here      print 'worker loop!'     #time.sleep(5)     try:         data in iter( self.queue.get, none ):             mid = data["_id"]             print "#" + self.idstr + " :  mongoid " + str(mid)             #time.sleep(5)             try:              timestamp = time.time()               document = {"rawdata": data,                                             "c": {                                             "quelle": "t",                                             "timestamp": mid.generation_time,                                             "query" :  data["query"]                                                                         }                                             }                      self.mongoconnection.insert("productive","input",document) 

update know tried pass in new document via constructor , use inside worker via self.document, sadly doesn't help.

one way of ensuring each worker thread isolated give each 1 own instance variable document. i.e. referencing document self.document.