[HAMA-352] Can't send one more messages on to same server in bsp() method

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.2.0
• Assignee: Edward J. Yoon
• Reporter: Edward J. Yoon
• Created: 14/Feb/11 13:11
• Updated: 05/Apr/11 10:33
• Resolved: 05/Apr/11 10:33

Description

Oh, thanks for nice report!

At this time, it looks like impossible to send one more messages on to
same server in bsp() method. It's a bug. I'll fix it now.

Pls, update your TRUNK.

---

To developers,

See the BSPPeer.send() method. The peerName should be a
InetSocketAddress, not String. Otherwise, queue will be always null.
And after add msg to queue, we have to put it to "outgoingQueues"
again as below:

— src/java/org/apache/hama/bsp/BSPPeer.java (revision 1069189)
+++ src/java/org/apache/hama/bsp/BSPPeer.java (working copy)
@@ -140,12 +140,12 @@
@Override
public void send(String peerName, BSPMessage msg) throws IOException {
LOG.debug("Send bytes (" + msg.getData().toString() + ") to " + peerName);

• ConcurrentLinkedQueue<BSPMessage> queue = outgoingQueues.get(peerName);
  + ConcurrentLinkedQueue<BSPMessage> queue =
  outgoingQueues.get(getAddress(peerName));
  if (queue == null) { queue = new ConcurrentLinkedQueue<BSPMessage>(); - outgoingQueues.put(getAddress(peerName), queue); }

  queue.add(msg);
  + outgoingQueues.put(getAddress(peerName), queue);

• Hide quoted text -
  }

On Mon, Feb 14, 2011 at 7:02 PM, Paweł Brach <[e-mail]> wrote:
> Hello,
>
> I'm attaching PiEstimator with some changes. I'm sending exactly two
> messages to "master" from each node.
>
> bspPeer.send(masterTask, estimate);
> LOG.info("Send message:" + System.currentTimeMillis());
> bspPeer.send(masterTask, estimate2);
> LOG.info("Send message:" + System.currentTimeMillis());
>
> After that I'm trying to receive all messages:
> LOG.info("Num msg = " + bspPeer.getNumCurrentMessages());
> while ((received = bspPeer.getCurrentMessage()) != null)

{ > LOG.info("Receives messages:" + Bytes.toDouble(received.getData())); > .... > }

>
> In the log file I see:
> 2011-02-14 09:46:07,124 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator: Send message:1297673167123
> 2011-02-14 09:46:07,125 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator: Send message:1297673167125
> 2011-02-14 09:46:07,270 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator: Receives messages:3.1536
> 2011-02-14 09:46:07,270 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator: Receives messages:3.148
> 2011-02-14 09:46:07,271 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator: Receives messages:3.1392
> 2011-02-14 09:46:07,272 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 11/02/14 09:46:07 INFO
> algorithms.PiEstimator$MyEstimator:
> 2011-02-14 09:46:07,272 INFO org.apache.hama.bsp.TaskRunner:
> attempt_201102140938_0003_m_000000_0 Estimated value of PI is
> 3.1450000000000005
>
>
> On each node I see that two messages are sent (so master should receive 6
> messages - I have 3 nodes). In the log file I see only 3 records
> "Receives...", so only 3 messages were processed by master task. I don'
> understand why is that.
>
> What's more, I have tried to change line:
> while ((received = bspPeer.getCurrentMessage()) != null) {
>
> to
> if ((received = bspPeer.getCurrentMessage()) != null) {
>
> So there should be messages in the queue which are not processed. In my
> opinion bsp() should be called again and again... and in consequence falls
> in loop of calls. But it doesn't happen - bsp() method is run exactly once
> and framework is probably hanging after last line of the bsp() code. Could
> you explain this for me?
>
> Best regards,
> Pawel
>