hama-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Thomas Jungblut (JIRA)" <j...@apache.org>
Subject [jira] [Created] (HAMA-633) Fix CI Failure
Date Mon, 20 Aug 2012 18:07:38 GMT
Thomas Jungblut created HAMA-633:
------------------------------------

             Summary: Fix CI Failure
                 Key: HAMA-633
                 URL: https://issues.apache.org/jira/browse/HAMA-633
             Project: Hama
          Issue Type: Bug
          Components: bsp core
    Affects Versions: 0.5.0
            Reporter: Thomas Jungblut
             Fix For: 0.6.0


The current nightly fails because it seems to read messages that actually belong to the previous
superstep.

This is reproducable also in the local runner, so this is no problem of the specific RPC implementations.
The problem could also be in the GraphJobRunner.

This is going to be expressed by a nullpointer exception, when a non-master tasks gets a aggregation
message (which actually just belongs to the master).

{noformat}
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 0 / hama.2;0 / 4
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.0

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 1 / hama.2;1 / 4

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.0
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 0 / hama.2;0 / 7
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.4572019638123739
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 1 / hama.2;1 / 7
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.44247448197562855

12/08/17 23:05:52 INFO server.PrepRequestProcessor: Got user-level KeeperException when processing
sessionid:0x13936d5d8cc0002 type:create cxid:0x3de zxid:0xfffffffffffffffe txntype:unknown
reqpath:n/a Error Path:/bsp/job_201208172305_0001/sync/51 Error:KeeperErrorCode = NodeExists
for /bsp/job_201208172305_0001/sync/51

12/08/17 23:05:52 INFO server.PrepRequestProcessor: Got user-level KeeperException when processing
sessionid:0x13936d5d8cc0002 type:create cxid:0x3e8 zxid:0xfffffffffffffffe txntype:unknown
reqpath:n/a Error Path:/bsp/job_201208172305_0001/sync/51/ready Error:KeeperErrorCode = NodeExists
for /bsp/job_201208172305_0001/sync/51/ready

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 0 / hama.2;0 / 4
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.0

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 1 / hama.2;1 / 4
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.0
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 0 / hama.2;0 / 7
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.457610574551534
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 1 / hama.2;1 / 7
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+  true janus.apache.org:61002
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________++ VAL=0.2675231554874198

12/08/17 23:05:52 INFO graph.GraphJobRunner: _________ 0 / hama.2;0 / 11
12/08/17 23:05:52 INFO graph.GraphJobRunner: _________+ NULL! false janus.apache.org:61001

12/08/17 23:05:52 ERROR bsp.BSPTask: Error running bsp setup and bsp function.
java.lang.NullPointerException
        at org.apache.hama.graph.GraphJobRunner.parseMessages(GraphJobRunner.java:373)
        at org.apache.hama.graph.GraphJobRunner.bsp(GraphJobRunner.java:209)
        at org.apache.hama.bsp.BSPTask.runBSP(BSPTask.java:166)
        at org.apache.hama.bsp.BSPTask.run(BSPTask.java:143)
        at org.apache.hama.bsp.GroomServer$BSPPeerChild.main(GroomServer.java:1271)

12/08/17 23:05:52 INFO server.PrepRequestProcessor: Processed session termination for sessionid:
0x13936d5d8cc0002

{noformat}

It is very difficult to track this down, my ideas were:

- It changes the host because of fault tolerance (contra arguments: its turned off and the
port is smaller than the other one)
- Messaging is broken (would also explain why pagerank does not converge anymore)

Some more info:

I know that this happens when the master tasks sends a message with the updated aggregator
values to every slave. (line 239). Then this only message should be consumed arround line
246 cc.

But it still remains in the buffer and will be consumed after all computation in line 209
in the parseMessages. 
Even clearing the buffer is not fixing it. 


The worst problem is, that this is not reproducable, the failure seems to happen just in only
two to three tenth of all builds. Seems like some really nasty edge case.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message