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Claus Köll commented on JCR-2554: --------------------------------- I have taken a look at JCR-1600 and JCR-447 where the code was introduced but i found no ground why this code was modified in that way to ignore the waitingWriters_ variable. I will change the code to work as the SuperClass should work. greets > Deadlock inside XASession on Weblogic > ------------------------------------- > > Key: JCR-2554 > URL: https://issues.apache.org/jira/browse/JCR-2554 > Project: Jackrabbit Content Repository > Issue Type: Bug > Components: jackrabbit-core > Affects Versions: 1.6.1, 2.0.0 > Environment: Weblogic 9.2 > Reporter: Robert Sauer > Assignee: Claus Köll > Priority: Critical > Fix For: 1.6.2, 2.1.0 > > Attachments: ConcurrentReaders.java, > jr-core-xid-aware-ism-locking1.patch, Xid.patch, Xid_v2 + SynchronizedRef for > markedXid.jpg, Xid_v2 deadlock.jpg, Xid_v2.patch, Xid_v3.patch, Xid_v4.patch > > > In one of our client deployments on WebLogic 9.2 we observed JackRabbit > sessions going stale in a load test. This was observed against release 1.6.1 > (to which we migrated due to concurrency related issues JCR-2081 and > JCR-2237). Same effect with 2.0.0. > > I could finally reproduce this issue locally. And it seems to boil down to > WLS invoking the sequence of <prepare> ... <release> ... <commit> on one XA > session from multiple threads, as it seems breaking assumptions of the > thread-bound java.util.concurrent-RWLock based DefaultISMLocking class. > Effectively the setActiveXid(..) method on DefaultISMLocking$RWLock fails as > the old active XID was not yet cleared. With the result of more and more > sessions deadlocking in below's invocation stack. > {code} > "[ACTIVE] ExecuteThread: '27' for queue: 'weblogic.kernel.Default > (self-tuning)'" daemon prio=1 tid=0x33fc3ec0 nid=0x2324 in Object.wait() > [0x2156a000..0x2156beb0] at java.lang.Object.wait(Native Method) - waiting on > <0x68a54698> (a > EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$WriterLock) at > java.lang.Object.wait(Object.java:474) at > EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$WriterLock.acquire(Unknown > Source) - locked <0x68a54698> (a > EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$WriterLock) at > org.apache.jackrabbit.core.state.DefaultISMLocking$1.<init>(DefaultISMLocking.java:64) > at > org.apache.jackrabbit.core.state.DefaultISMLocking.acquireWriteLock(DefaultISMLocking.java:61) > at > org.apache.jackrabbit.core.version.AbstractVersionManager.acquireWriteLock(AbstractVersionManager.java:146) > at > org.apache.jackrabbit.core.version.XAVersionManager$1.prepare(XAVersionManager.java:562) > at > org.apache.jackrabbit.core.TransactionContext.prepare(TransactionContext.java:154) > - locked <0x6dc2ad88> (a org.apache.jackrabbit.core.TransactionContext) at > org.apache.jackrabbit.core.XASessionImpl.prepare(XASessionImpl.java:331) at > org.apache.jackrabbit.jca.TransactionBoundXAResource.prepare(TransactionBoundXAResource.java:68) > at > weblogic.connector.security.layer.AdapterLayer.prepare(AdapterLayer.java:397) > at > weblogic.connector.transaction.outbound.XAWrapper.prepare(XAWrapper.java:297) > at > weblogic.transaction.internal.XAServerResourceInfo.prepare(XAServerResourceInfo.java:1276) > at > weblogic.transaction.internal.XAServerResourceInfo.prepare(XAServerResourceInfo.java:499) > at > weblogic.transaction.internal.ServerSCInfo$1.execute(ServerSCInfo.java:335) > at weblogic.kernel.Kernel.executeIfIdle(Kernel.java:243) at > weblogic.transaction.internal.ServerSCInfo.startPrepare(ServerSCInfo.java:326) > at > weblogic.transaction.internal.ServerTransactionImpl.localPrepare(ServerTransactionImpl.java:2516) > at > weblogic.transaction.internal.ServerTransactionImpl.globalPrepare(ServerTransactionImpl.java:2211) > at > weblogic.transaction.internal.ServerTransactionImpl.internalCommit(ServerTransactionImpl.java:266) > at > weblogic.transaction.internal.ServerTransactionImpl.commit(ServerTransactionImpl.java:227) > at > weblogic.transaction.internal.TransactionManagerImpl.commit(TransactionManagerImpl.java:283) > at > org.springframework.transaction.jta.JtaTransactionManager.doCommit(JtaTransactionManager.java:1028) > at > org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:709) > at > org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:678) > {code} -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.