ZeroMQ Stream -> stack guard problem and no data

[Tobias Pfeiffer]

Hi,

I am trying to use Spark Streaming (1.0.0) with ZeroMQ, i.e. I say

    def bytesToStringIterator(x: Seq[ByteString]) =
(x.map(_.utf8String)).iterator
    val lines: DStream[String] =
      ZeroMQUtils.createStream(ssc,
        "tcp://localhost:5556",
        Subscribe("mytopic"),
        bytesToStringIterator _)
    lines.print()

but when I start this program (in local mode), I get

OpenJDK 64-Bit Server VM warning: You have loaded library
/tmp/jna2713405829859698528.tmp which might have disabled stack guard.
The VM will try to fix the stack guard now.
It's highly recommended that you fix the library with 'execstack -c
<libfile>', or link it with '-z noexecstack'.

and no data is received. The ZeroMQ setup should be ok, though; the Python code

    context = zmq.Context()
    socket = context.socket(zmq.SUB)
    socket.setsockopt(zmq.SUBSCRIBE, "mytopic")
    socket.connect("tcp://localhost:5556")
    while True:
        msg = socket.recv()
        print msg
        time.sleep(1)

works fine and prints the messages issued by the publisher.

Any suggestions on what is going wrong here?

Thanks
Tobias