[GIRAPH-386] ClassCastException when giraph.SplitMasterWorker=false

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Assignee: Maja Kabiljo
• Reporter: Jaeho Shin
• Created: 24/Oct/12 23:31
• Updated: 13/Nov/12 23:28
• Resolved: 13/Nov/12 23:28

Description

Using -Dgiraph.SplitMasterWorker=false with a recent trunk (r1401165) caused the machine who is playing the master role (showing itself as ALL from the task tracker page) to throw ClassCastException (SendVertexRequest -> MasterRequest) from MasterRequestServerHandler class. I'm trying to use as many machines as possible for actual computation (can't afford to waste one for master+ZK). This worked fine with r1388628 (roughly a month ago), so a recent change must've broken something. Here's the relevant log I captured:

2012-10-24 23:08:02,152 WARN org.apache.giraph.comm.netty.handler.RequestServerHandler: exceptionCaught: Channel failed with remote address /10.x.y.z:41780
java.lang.ClassCastException: org.apache.giraph.comm.requests.SendVertexRequest cannot be cast to org.apache.giraph.comm.requests.MasterRequest
	at org.apache.giraph.comm.netty.handler.MasterRequestServerHandler.processRequest(MasterRequestServerHandler.java:25)
	at org.apache.giraph.comm.netty.handler.RequestServerHandler.messageReceived(RequestServerHandler.java:100)
	at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
	at org.jboss.netty.handler.codec.oneone.OneToOneDecoder.handleUpstream(OneToOneDecoder.java:71)
	at org.jboss.netty.handler.execution.ChannelUpstreamEventRunnable.doRun(ChannelUpstreamEventRunnable.java:45)
	at org.jboss.netty.handler.execution.ChannelEventRunnable.run(ChannelEventRunnable.java:69)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:662)

Issue Links

• relates to: GIRAPH-362 Address master task id for communication for master (known issue from GIRAPH-211)