Hi,

we are using hibernate 3

we have a web applicaiton which runs on four concurrent server for load balancing
when we try to do performance testing, try to load test it with 25 users
i mean 25 user will try to login and logout concurrently
upto 20 users we didn't face any error but after 21st user login we are getting some error
we could able to resolve this issue

10-11-25 11:55:20,029 ERROR tcp-connection-x.x.x.x:6815-37 AbstractFlushingEventListener:277 - Could not synchronize database state with session
org.hibernate.exception.GenericJDBCException: could not delete: [com.three.sso.service.db.basic.ST#ST-290-143HpJCEWWShaIh1tPEx]
at org.hibernate.exception.ErrorCodeConverter.handledNonSpecificException(ErrorCodeConverter.java:92)
at org.hibernate.exception.ErrorCodeConverter.convert(ErrorCodeConverter.java:80)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.persister.entity.BasicEntityPersister.delete(BasicEntityPersister.java:2086)
at org.hibernate.persister.entity.BasicEntityPersister.delete(BasicEntityPersister.java:2213)
at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:59)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:239)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:223)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:141)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:274)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:730)
at com.three.sso.service.db.DataCommandExecutor.executeCommand(DataCommandExecutor.java:56)
at com.three.sso.service.db.basic.BasicSingleSignOnService.deleteST(BasicSingleSignOnService.java:505)
at edu.yale.its.tp.cas.ticket.ServiceTicketCache.deleteST(ServiceTicketCache.java:200)
at com.three.ssoserver.servlet.SSOServiceValidate.doGet(SSOServiceValidate.java:134)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:115)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:92)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:106)
at com.caucho.server.webapp.DispatchFilterChain.doFilter(DispatchFilterChain.java:115)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:229)
at com.caucho.server.webapp.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:277)
at com.caucho.server.webapp.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:106)
at com.three.ssoserver.servlet.SSOProxyValidate.doGet(SSOProxyValidate.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:115)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:92)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:106)
at com.three.sprint.performance.filter.PerformanceFilter.doFilter(PerformanceFilter.java:47)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70)
at com.three.sso.logging.filter.LoggingFilter.doFilter(LoggingFilter.java:66)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:173)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:229)
at com.caucho.server.hmux.HmuxRequest.handleRequest(HmuxRequest.java:420)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:511)
at com.caucho.util.ThreadPool.runTasks(ThreadPool.java:520)
at com.caucho.util.ThreadPool.run(ThreadPool.java:442)
at java.lang.Thread.run(Thread.java:595)
Caused by: java.sql.SQLException: ORA-08177: can't serialize access for this transaction
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
at oracle.jdbc.ttc7.TTIoer.processError(TTIoer.java:289)
at oracle.jdbc.ttc7.Oall7.receive(Oall7.java:579)
at oracle.jdbc.ttc7.TTC7Protocol.doOall7(TTC7Protocol.java:1894)
at oracle.jdbc.ttc7.TTC7Protocol.parseExecuteFetch(TTC7Protocol.java:1094)
at oracle.jdbc.driver.OracleStatement.executeNonQuery(OracleStatement.java:2132)
at oracle.jdbc.driver.OracleStatement.doExecuteOther(OracleStatement.java:2015)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:2877)
at oracle.jdbc.driver.OraclePreparedStatement.executeUpdate(OraclePreparedStatement.java:608)
at org.hibernate.jdbc.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:22)
at org.hibernate.persister.entity.BasicEntityPersister.delete(BasicEntityPersister.java:2069)
... 34 more



Can some one help us on resolving this. Are we missing some configuration?

Thanks in advance
vijaykarthik.

Found the solution :-)

We just changed the hibernate.isolation level from 8 to 2 , that solves the error.

<prop key="hibernate.connection.isolation">8</prop>
to
<prop key="hibernate.connection.isolation">2</prop>