Re: TR: [jira] Created: (OPENEJB-1049) Stateful session cache management issue

David Blevins Wed, 23 Sep 2009 02:36:18 -0700


On Sep 1, 2009, at 8:33 PM, David Blevins wrote:

Been looking into this one and not too sure how we want to deal withit. We definitely want to fix it for our 3.1.2 release. I've had alook at our 3.0.x logic and we do allow this scenario though thespec sort of says it should result in an "error" though never sayswhat the error should be. I like the 3.0.x behavior of allowingsomeone executing a stateful bean in a transaction to pause thetransaction and still be able to use the stateful bean.
We've had 3.1.x out for a while but 3.1.2 will be Geronimo's firstrelease since 3.0.x so this could pose a compatibility issue forusers upgrading -- I can't imagine anyone being too happy abouthaving to rewrite transaction logic.
Racking my brain on how best to fix this.

Went back at this issue the last couple days and it's looking to bevery difficult to retain the behavior we had in 3.0 with the way thenew code is written.

Having dug deeper into the issue the problem is not with theSimpleCache code but rather asymmetry in the obtainInstance() andreleaseInstance() methods. Specifically, the checkedOutInstances mapand related code which is getting used as a secondary cache and isn'twell managed. There are other issues with the code such as it ispossible for another thread outside your to remove your statefulinstance. That's a rather big no-no as lots of stateful code isdesigned to flush data in the beforeCompletion() and well, you needthe instance for that. Basically, the current code protects againstthe instance being used by multiple threads at the same time, but doesnot protect against it being used by multiple transactions at the sametime.


Going to keep hacking on it tomorrow.

-David


-David

On Aug 24, 2009, at 12:53 AM, Jean-Louis MONTEIRO wrote:


Hi David,

Finally, i've got the time to dig into this issue.
This exception occurs when from a session bean you call a SFSB. More
precisely, it's linked with transaction/cache management when the
transaction must be suspended in the stateful.

REQUIRED -> REQUIRES_NEW
REQUIRED -> NOT_SUPPORTED
REQUIRES_NEW-> REQUIRES_NEW
REQUIRES_NEW-> NOT_SUPPORTED

For those cases, the releaseInstance from the StatefulContainerseems to becalled both for JtaTransactionPolicy of the stateful as well as forthe

first session bean.

It results in an exception because we try to checkIn the sameinstance in

the Cache 2 times.

Jean-Louis



David Blevins wrote:


Hi Jean-Louis,

Can't seem to get the time to take a detailed look.  Is it possible

you could give a brief walkthrough of what is happening and thecause?



-David


On Jul 6, 2009, at 7:03 AM, Monteiro Jean-Louis wrote:

I change simple-stateless and simple-stateful examples to reproduce
this issue.

Jean-Louis



-----Message d'origine-----
De : Jean-Louis MONTEIRO (JIRA) [mailto:[email protected]]
Envoyé : lundi 6 juillet 2009 16:02
À : Monteiro Jean-Louis
Objet : [jira] Created: (OPENEJB-1049) Stateful session cache
management issue

Stateful session cache management issue
---------------------------------------

              Key: OPENEJB-1049
              URL: https://issues.apache.org/jira/browse/
OPENEJB-1049
          Project: OpenEJB
       Issue Type: Bug
 Affects Versions: 3.1.1
         Reporter: Jean-Louis MONTEIRO


SimpleCache throws an error during check in.

ERROR - An unexpected system exception occured while invoking the
afterCompletion method on the SessionSynchronization object
java.lang.IllegalStateException: The entry
d52b726a0e36ac50:-3f5aa6df:122503062bb:-8000 is not checked-out
     at
org
.apache.openejb.core.stateful.SimpleCache.checkIn(SimpleCache.java:
219)
     at
org
.apache
.openejb
.core
.stateful.StatefulContainer.releaseInstance(StatefulContainer.java:
659)
     at org.apache.openejb.core.stateful.StatefulContainer.access
$2(StatefulContainer.java:646)
     at org.apache.openejb.core.stateful.StatefulContainer
$
SessionSynchronizationCoordinator
.afterCompletion(StatefulContainer.java:940)
     at org.apache.openejb.core.transaction.JtaTransactionPolicy
$1.afterCompletion(JtaTransactionPolicy.java:155)
     at
org
.apache
.geronimo
.transaction
.manager.TransactionImpl.afterCompletion(TransactionImpl.java:534)
     at
org
.apache
.geronimo
.transaction
.manager.TransactionImpl.afterCompletion(TransactionImpl.java:526)
     at
org
.apache
.geronimo

.transaction.manager.TransactionImpl.commit(TransactionImpl.java:326)

     at
org
.apache
.geronimo
.transaction
.manager.TransactionManagerImpl.commit(TransactionManagerImpl.java:
245)
     at
org
.apache
.openejb
.core
.transaction

.JtaTransactionPolicy.completeTransaction(JtaTransactionPolicy.java:

291)
     at
org

.apache.openejb.core.transaction.TxRequired.commit(TxRequired.java:71)

     at
org
.apache
.openejb
.core

.transaction.EjbTransactionUtil.afterInvoke(EjbTransactionUtil.java:

74)
     at
org
.apache
.openejb
.core.stateless.StatelessContainer._invoke(StatelessContainer.java:
241)
     at
org
.apache
.openejb

.core.stateless.StatelessContainer.invoke(StatelessContainer.java:174)

     at
org
.apache
.openejb
.core

.ivm.EjbObjectProxyHandler.businessMethod(EjbObjectProxyHandler.java:

217)
     at
org
.apache
.openejb

.core.ivm.EjbObjectProxyHandler._invoke(EjbObjectProxyHandler.java:77)

     at
org
.apache
.openejb
.core.ivm.BaseEjbProxyHandler.invoke(BaseEjbProxyHandler.java:281)
     at $Proxy10.sum(Unknown Source)
     at
org
.superbiz
.calculator

.CalculatorTest.testCalculatorViaRemoteInterface(CalculatorTest.java:

51)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at
sun
.reflect
.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
     at
sun
.reflect
.DelegatingMethodAccessorImpl
.invoke(DelegatingMethodAccessorImpl.java:25)
     at java.lang.reflect.Method.invoke(Method.java:585)
     at junit.framework.TestCase.runTest(TestCase.java:164)
     at junit.framework.TestCase.runBare(TestCase.java:130)
     at junit.framework.TestResult$1.protect(TestResult.java:110)

at junit.framework.TestResult.runProtected(TestResult.java:128)

     at junit.framework.TestResult.run(TestResult.java:113)
     at junit.framework.TestCase.run(TestCase.java:120)
     at junit.framework.TestSuite.runTest(TestSuite.java:228)
     at junit.framework.TestSuite.run(TestSuite.java:223)
     at
org
.junit

.internal.runners.OldTestClassRunner.run(OldTestClassRunner.java:35)

     at
org
.eclipse
.jdt
.internal
.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
     at
org
.eclipse
.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
     at
org
.eclipse
.jdt
.internal
.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
     at
org
.eclipse
.jdt
.internal
.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
     at
org
.eclipse
.jdt

.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)

     at
org
.eclipse
.jdt
.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:
197)
WARN - Unexpected exception from afterCompletion; continuing
java.lang.RuntimeException: An unexpected system exception occured
while invoking the afterCompletion method on the
SessionSynchronization object
     at org.apache.openejb.core.stateful.StatefulContainer
$
SessionSynchronizationCoordinator
.afterCompletion(StatefulContainer.java:962)
     at org.apache.openejb.core.transaction.JtaTransactionPolicy
$1.afterCompletion(JtaTransactionPolicy.java:155)
     at
org
.apache
.geronimo
.transaction
.manager.TransactionImpl.afterCompletion(TransactionImpl.java:534)
     at
org
.apache
.geronimo
.transaction
.manager.TransactionImpl.afterCompletion(TransactionImpl.java:526)
     at
org
.apache
.geronimo