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JBoss cache / concurrent creation event
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created by <a href="http://community.jboss.org/people/brettcave">Brett Cave</a> in <i>JBoss Cache</i> - <a href="http://community.jboss.org/message/564341#564341">View the full discussion</a>
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<div class="jive-rendered-content"><p>We have been having an issue with this for quite some time, and I am battling to understand the cause of the issue, hoping someone could help explain and work a solution for this.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>While using a web application an exception occassionally occurs:</p><p>2010-09-30 14:12:27,901 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/]] (ajp-0.0.0.0-8009-2) Exception while dispatching incoming RPC call</p><p>com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract com.mycompany.web.common.client.model.rank.RankResponse com.mycompany.web.common.client.rpc.Ranking<br/>Service.rank(java.lang.String,int,com.mycompany.web.common.client.model.rank.RankRequestProperties,java.util.Map,java.util.Map,java.util.Map,java.util.Map)' threw an unexpected exception: javax.ejb.EJBTransactionRolledbackException: Transaction rolled back</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>Just prior to that in the log, the following is seen:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>2010-09-30 14:12:27,895 WARN  [org.jboss.cache.interceptors.OptimisticTxInterceptor] (ajp-0.0.0.0-8009-2) Caught exception, will now set transaction to roll back<br/>org.jboss.cache.optimistic.DataVersioningException: Transaction attempted to create /adonis/org/hibernate/cache/StandardQueryCache/QUERY/sql: select <QUERY DETAILS>; max rows: 2 anew.  It has already been created since this transaction started, by another (possibly remote) transaction.<br/>We have a concurrent creation event.<br/>        at org.jboss.cache.interceptors.OptimisticValidatorInterceptor.visitOptimisticPrepareCommand(OptimisticValidatorInterceptor.java:116)</p><p>....</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>2010-09-30 14:12:27,897 WARN  [com.arjuna.ats.arjuna.logging.arjLoggerI18N] (ajp-0.0.0.0-8009-2) [com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator_2] TwoPhaseCoordinator.beforeCompletion - failed for com.arjuna.ats.internal.jta.resources.arjunacore.SynchronizationImple@493ee8c1<br/>org.jboss.cache.optimistic.DataVersioningException: Transaction attempted to create /adonis/org/hibernate/cache/StandardQueryCache/QUERY/sql: select <QUERY DETAILS>; max rows: 2 anew.  It has already been created since this transaction started, by another (possibly remote) transaction.<br/>We have a concurrent creation event.<br/>        at org.jboss.cache.interceptors.OptimisticValidatorInterceptor.visitOptimisticPrepareCommand(OptimisticValidatorInterceptor.java:116)</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>Environment:</p><p>The application is deployed in an ear with an ejb and war component.</p><p>The ejb has a persistence unit, which uses an XA jta-datasource and 3 entity jar-files defined (that are deployed independantly)</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>Another application is deployed that the primary application depends on, an EAR with ejb and persistence. The persistence unit references a different XA datasource and references 1 of the 3 jar-files as above.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>The issue might be caused by having 2 persistence contexts being applied to a single entity, but not entirely sure on this though</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>I have tried adjusting the transaction manger's configuration to allowMultipleLastResources = true (before we switched to XA datasources, this was necessary with tx datasources and this environment), but the error occurs with this enabled or disabled.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>I am not sure whether this is a jboss cache issue, hibernate or transaction manager issue.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>how could I avoid this issue? (the exception occurs irregularly, it's difficult to reproduce).</p></div>
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<p style="margin: 0;">Reply to this message by <a href="http://community.jboss.org/message/564341#564341">going to Community</a></p>
<p style="margin: 0;">Start a new discussion in JBoss Cache at <a href="http://community.jboss.org/choose-container!input.jspa?contentType=1&containerType=14&container=2052">Community</a></p>
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