Re: [Springframework-developer] Non Thread-safe hibernate session

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It seems unlikely that this is a problem with Spring - those threads are 
created by Tomcat and not Spring. I am wondering however if at that 
level of load the ThreadLocal stuff isn't getting cleared somehow when a 
thread is put back in the pool? Is this possible?

Rob

March, Andres wrote:

> Unfortunately, this is not the case here. We are using jmeter with 
> unauthenticated requests and therefore put nothing in the httpsession. 
> Additionally, your example should take place with as little as 2 
> requests: one fetching the object and sticking it into the 
> HttpSession, the other trying to initialize its collections. In our 
> case, we have to create a decent amount of load (~30 pages/sec) for 
> the errors to occur. Any other ideas?
>
> ------------------------------------------------------------------------
>
> *From:* spr...@li... 
> [mailto:spr...@li...] *On 
> Behalf Of *Juergen Hoeller
> *Sent:* Saturday, January 29, 2005 2:44 AM
> *To:* spr...@li...
> *Subject:* RE: [Springframework-developer] Non Thread-safe hibernate 
> session
>
> Actually, this can happen without either Spring or the ThreadLocal 
> mechanism breaking: One of your persistent objects might hold a lazy 
> persistent collection, which holds a reference to the Session that 
> originally loaded it.
>
> If you put such a persistent object into the HttpSession, for example, 
> the original request that loaded the object (in thread TPProcessor1) 
> will have completed and thus the Hibernate Session have been closed. 
> Now, if you take your persistent object out of the HttpSession again 
> in a new request (in thread TPProcessor7) and try to access it lazy 
> collection, it's gonna fail because the original Session has been closed.
>
> So the "leak" where a Session reference got out of its original 
> request/thread context is your persistent object in the HttpSession 
> here. This is a well-known problem: To make lazy loading work here, 
> you need to attach the persistent object to the new Hibernate Session 
> (via lock or saveOrUpdate).
>
> Juergen
>
>     -----Original Message-----
>     *From:* spr...@li...
>     [mailto:spr...@li...]*On
>     Behalf Of *March, Andres
>     *Sent:* Friday, January 28, 2005 8:27 PM
>     *To:* spr...@li...
>     *Subject:* [Springframework-developer] Non Thread-safe hibernate
>     session
>
>     As you can see below, a thread, other than the one that had the
>     session created for it, tries to access a session but it has been
>     closed by the valid owner thread. This only occurs under decent
>     load. There must be some thread safety issue in Spring or the
>     whole ThreadLocal idea goes out the window. Does anybody have any
>     idea how this could occur? I don’t see how I could be
>     misinterpreting this trace.
>
>     FATAL (SessionImpl.java:528) - Constructor for session:
>     net.sf.hibernate.impl.SessionImpl@b72884 on thread : TP-Processor1
>
>     FATAL (SessionFactoryImpl.java:342) - Session :
>     net.sf.hibernate.impl.SessionImpl@b72884 created for Thread :
>     TP-Processor1
>
>     …later on…
>
>     closing session : net.sf.hibernate.impl.SessionImpl@b72884 and
>     conn: com.mchange.v2.c3p0.impl.NewProxyConnection@4ad009 on Thread
>     : TP-Processor1
>
>     …later on…
>
>     net.sf.hibernate.HibernateException: Session is closed :
>     net.sf.hibernate.impl.SessionImpl@b72884 on thread : TP-Processor7
>
>     at net.sf.hibernate.impl.SessionImpl.connection(SessionImpl.java:3313)
>
>     at
>     net.sf.hibernate.proxy.LazyInitializer.initialize(LazyInitializer.java:47)
>
>     at
>     net.sf.hibernate.proxy.LazyInitializer.initializeWrapExceptions(LazyInitializer.java:60)
>
>     at
>     net.sf.hibernate.proxy.LazyInitializer.getImplementation(LazyInitializer.java:164)
>
>     at
>     net.sf.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:108)
>
>     at
>     com.sony.soe.guilds.model.GameCharacter$$EnhancerByCGLIB$$25b6cd13.getBioImage(<generated>)
>
>     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:324)
>
>     at
>     org.apache.velocity.runtime.parser.node.PropertyExecutor.execute(PropertyExecutor.java:111)
>
>     at
>     org.apache.velocity.util.introspection.UberspectImpl$VelGetterImpl.invoke(UberspectImpl.java:300)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTIdentifier.execute(ASTIdentifier.java:157)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:175)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTReference.evaluate(ASTReference.java:307)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTNotNode.evaluate(ASTNotNode.java:47)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTExpression.evaluate(ASTExpression.java:46)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:69)
>
>     at
>     org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:231)
>
>     at org.apache.velocity.runtime.directive.Parse.render(Parse.java:181)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:116)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:56)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:71)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:56)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:71)
>
>     at
>     org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:231)
>
>     at org.apache.velocity.runtime.directive.Parse.render(Parse.java:181)
>
>     at
>     org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:116)
>
>     at
>     org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:231)
>
>     at org.apache.velocity.Template.merge(Template.java:256)
>
>     at com.sony.soe.web.mvc.VelocityView.go(VelocityView.java:181)
>
>     at com.sony.soe.guilds.view.VelocityLayout.go(VelocityLayout.java:135)
>
>     at org.infohazard.maverick.flow.CommandBase.go(CommandBase.java:79)
>
>     at org.infohazard.maverick.Dispatcher.service(Dispatcher.java:345)
>
>     at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
>
>     at
>     net.sf.acegisecurity.ui.AbstractIntegrationFilter.doFilter(AbstractIntegrationFilter.java:170)
>
>     at
>     com.sony.soe.guilds.controller.SecurityFilter.doFilter(SecurityFilter.java:118)
>
>     at
>     net.sf.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:88)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:186)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
>
>     at
>     org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:17
>
>     1)
>
>     at
>     org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:186)
>
>     at
>     org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
>
>     at
>     org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>
>     at
>     org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>
>     at
>     org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
>
>     at
>     org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>
>     at
>     org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>
>     at
>     org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>
>     at
>     org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
>
>     at
>     org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>
>     at
>     org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>
>     at
>     org.apache.catalina.valves.RequestDumperValve.invoke(RequestDumperValve.java:169)
>
>     at
>     org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
>
>     at
>     org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>
>     at
>     org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
>
>     at
>     org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
>
>     at
>     org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:296)
>
>     at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:372)
>
>     at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:694)
>
>     at
>     org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:626)
>
>     at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:807)
>
>     at
>     org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:644)
>
>     at java.lang.Thread.run(Thread.java:534)
>
>     -----------------------------------------
>
>     Andres March
>
>     Platform - Apps Engineering
>
>     Sony Online Entertainment
>
>     desk: 858.577.3373
>
>     cell: 619.519.1519
>