upstream/ipython Files · docs/examples/newparallel/demo/noncopying.py

tasks on engines when they die fail instead of hang...

tasks on engines when they die fail instead of hang This is only true in the Python scheduler, and not for any ZMQ scheduler (MUX,control,pure)

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      """non-copying sends"""

      import zmq

      import numpy

      n = 10

      iface = 'inproc://pub'

      ctx = zmq.Context()

      p = ctx.socket(zmq.PUB)

      p.bind(iface)

      # connect 2 subs

      s1 = ctx.socket(zmq.SUB)

      s1.connect(iface)

      s1.setsockopt(zmq.SUBSCRIBE, '')

      s2 = ctx.socket(zmq.SUB)

      s2.connect(iface)

      s2.setsockopt(zmq.SUBSCRIBE, '')

      A = numpy.random.random((1024,1024))

      # send

      p.send(A, copy=False)

      # recv on 1 non-copy

      msg1 = s1.recv(copy=False)

      B1 = numpy.frombuffer(msg1.buffer, dtype=A.dtype).reshape(A.shape)

      # recv on 2 copy

      msg2 = s2.recv(copy=False)

      B2 = numpy.frombuffer(buffer(msg2.bytes), dtype=A.dtype).reshape(A.shape)

      print (B1==B2).all()

      print (B1==A).all()

      A[0][0] += 10

      print "~"

      # after changing A in-place, B1 changes too, proving non-copying sends

      print (B1==A).all()

      # but B2 is fixed, since it called the msg.bytes attr, which copies

      print (B1==B2).all()

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				"""non-copying sends"""
				import zmq
				import numpy

				n = 10
				iface = 'inproc://pub'

				ctx = zmq.Context()

				p = ctx.socket(zmq.PUB)
				p.bind(iface)

				# connect 2 subs
				s1 = ctx.socket(zmq.SUB)
				s1.connect(iface)
				s1.setsockopt(zmq.SUBSCRIBE, '')

				s2 = ctx.socket(zmq.SUB)
				s2.connect(iface)
				s2.setsockopt(zmq.SUBSCRIBE, '')

				A = numpy.random.random((1024,1024))

				# send
				p.send(A, copy=False)
				# recv on 1 non-copy
				msg1 = s1.recv(copy=False)
				B1 = numpy.frombuffer(msg1.buffer, dtype=A.dtype).reshape(A.shape)
				# recv on 2 copy
				msg2 = s2.recv(copy=False)
				B2 = numpy.frombuffer(buffer(msg2.bytes), dtype=A.dtype).reshape(A.shape)

				print (B1==B2).all()
				print (B1==A).all()
				A[0][0] += 10
				print "~"
				# after changing A in-place, B1 changes too, proving non-copying sends
				print (B1==A).all()
				# but B2 is fixed, since it called the msg.bytes attr, which copies
				print (B1==B2).all()