Hi Aapo,
Thanks for the error report. I think you found a bug. Can you try the
included patch and see if the problem goes away? I got it to pass local
and MR unittests.
Avery
On 9/30/11 4:08 PM, Aapo Kyrola wrote:
Hi,
occasionally (maybe one time in four), my giraph run fails because of
the below RuntimeException.
According to code, it should never happen:
if (msgMap == null) { // should never happen after constructor throw
new RuntimeException( "sendMessage: msgMap did not exist for " + addr
+ " for vertex " + destVertex); }
This happens during superstep 1 (second superstep). My application
actually *adds* edges on superstep 1
(to make every out-edge also an in-edge of the destination), but since
I am running only on 3 workers,
I am surprised if every worker would not had been registered in the
RPC layer initially.
One hypothesis is that Hadoop does something funny, because one of my
server was under heavy
load. Maybe Hadoop launched another worker to replace a slow worker?
Can it happen?
java.lang.RuntimeException: sendMessage: msgMap did not exist for
[hostname].ml.cmu.edu:30003 for vertex 875713
at
org.apache.giraph.comm.BasicRPCCommunications.sendMessageReq(BasicRPCCommunications.java:825)
at
org.apache.giraph.graph.BasicVertex.sendMsg(BasicVertex.java:179)
at
edu.cmu.selectlab.BP.BinaryBPVertex.compute(BinaryBPVertex.java:94)
at org.apache.giraph.graph.GraphMapper.map(GraphMapper.java:624)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:763)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:369)
at org.apache.hadoop.mapred.Child$4.run(Child.java:259)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059)
at org.apache.hadoop.mapred.Child.main(Child.java:253)
Aapo Kyrola
Ph.D. student, http://www.cs.cmu.edu/~akyrola
<http://www.cs.cmu.edu/%7Eakyrola>
Index: src/main/java/org/apache/giraph/graph/GraphMapper.java
===================================================================
--- src/main/java/org/apache/giraph/graph/GraphMapper.java (revision
1177497)
+++ src/main/java/org/apache/giraph/graph/GraphMapper.java (working copy)
@@ -562,7 +562,7 @@
" maxMem=" + Runtime.getRuntime().maxMemory() +
" freeMem=" + Runtime.getRuntime().freeMemory());
}
- if ((superstep > BspService.INPUT_SUPERSTEP) &&
+ if ((superstep >= BspService.INPUT_SUPERSTEP) &&
(commService == null)) {
if (LOG.isInfoEnabled()) {
LOG.info("map: Starting communication service on " +
