Wso2 BPS: No such channel Error

Question

I'm using wso2 bps 2.1.2 for running simple bpel process with tree invokes called one by one in loop. The loop is around one hundred times. Problem is that sometimes process hang in running state. In logs I get error:

[2013-03-25 14:44:17,897] ERROR - BpelEngineImpl - Scheduled job failed; jobDetail=JobDetails( instanceId: 14109433 mexId: null processId: null type: TIMER channel: 11513 correlatorId: null correlationKeySet: null retryCount: null inMem: false detailsExt: {})
java.lang.IllegalArgumentException: No such channel; id=11513
    at org.apache.ode.jacob.vpu.ExecutionQueueImpl.findChannelFrame(ExecutionQueueImpl.java:205)
    at org.apache.ode.jacob.vpu.ExecutionQueueImpl.consumeExport(ExecutionQueueImpl.java:232)
    at org.apache.ode.jacob.vpu.JacobVPU$JacobThreadImpl.importChannel(JacobVPU.java:369)
    at org.apache.ode.jacob.JacobObject.importChannel(JacobObject.java:47)
    at org.apache.ode.bpel.engine.BpelRuntimeContextImpl$5.run(BpelRuntimeContextImpl.java:964)
    at sun.reflect.GeneratedMethodAccessor44.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
    at java.lang.reflect.Method.invoke(Method.java:611)
    at org.apache.ode.jacob.vpu.JacobVPU$JacobThreadImpl.run(JacobVPU.java:451)
    at org.apache.ode.jacob.vpu.JacobVPU.execute(JacobVPU.java:139)
    at org.apache.ode.bpel.engine.BpelRuntimeContextImpl.execute(BpelRuntimeContextImpl.java:879)
    at org.apache.ode.bpel.engine.BpelRuntimeContextImpl.timerEvent(BpelRuntimeContextImpl.java:968)
    at org.apache.ode.bpel.engine.BpelProcess.handleJobDetails(BpelProcess.java:478)
    at org.apache.ode.bpel.engine.BpelEngineImpl.onScheduledJob(BpelEngineImpl.java:560)
    at org.apache.ode.bpel.engine.BpelServerImpl.onScheduledJob(BpelServerImpl.java:445)
    at org.apache.ode.scheduler.simple.SimpleScheduler$RunJob$1.call(SimpleScheduler.java:537)
    at org.apache.ode.scheduler.simple.SimpleScheduler$RunJob$1.call(SimpleScheduler.java:531)
    at org.apache.ode.scheduler.simple.SimpleScheduler.execTransaction(SimpleScheduler.java:284)
    at org.apache.ode.scheduler.simple.SimpleScheduler.execTransaction(SimpleScheduler.java:239)
    at org.apache.ode.scheduler.simple.SimpleScheduler$RunJob.call(SimpleScheduler.java:531)
    at org.apache.ode.scheduler.simple.SimpleScheduler$RunJob.call(SimpleScheduler.java:515)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:314)
    at java.util.concurrent.FutureTask.run(FutureTask.java:149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:897)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:919)
    at java.lang.Thread.run(Thread.java:738)

I can't find any useful information about this error. I'm using oracle database. I tried to modify bps.xml with:

<tns:OpenJPAConfig>
  <tns:property name="openjpa.FlushBeforeQueries" value="true"/>
  <!-- added this line as for https://wso2.org/jira/browse/CARBON-7500  (use also Oracle 11g Driver!!) -->
  <tns:property name="openjpa.jdbc.DBDictionary" value="oracle(batchLimit=0)"/>
</tns:OpenJPAConfig>

But this didn't help.

Process is really simple it look like this:

<forEach counterName="count"  parallel="no" >

    < doXslTransform …>
    <wait 1s>
    <invoke ...>

    <doXslTransform …>
    <wait 1s>
    <invoke ...>

    < doXslTransform …>
    <wait 1s>
    <invoke ...>
</forEach>

How can I solve “No such channel” errors?

Thanks Tomek

Answer 1

We identified one issue that was causing this problem and fixed it. It was due to a missing process instance lock in the ode run-time embedded within BPS. We found this issue and fixed it.

https://issues.apache.org/jira/browse/ODE-989

https://wso2.org/jira/browse/BPS-218

If you can attach your sample scenario to the jira, it would help us add another test case. The fix is already available in the trunk and will be available in the next release.

Regards Nandika

Answer 2

I had remove waits from process and everything start working without problems. It seems that there is some bug in < wait > activity in WSO2 BPS 2.1.2. In BPS 3.0.0 it seams that waits are working.