[jbosscache-dev] Bug in 2.1.1.CR4 CacheLoader region-based unmarshalling

[Brian Stansberry]

Looks like this was due to a temporary bug I introduced in the AS 
testsuite as I was refactoring it over the weekend; one test's FCL was 
writing to a directory not using region-based marshalling and another 
test later used a region-based marshalling cache pointed at the same 
directory tree.  This has been fixed.

Sorry for the noise; thanks Manik for looking into it.

Brian Stansberry wrote:
> Seeing problems in region-based marshalling/unmarshalling with 
> FileCacheLoader[1].
> 
> Looking at the code, it looks like when doing a write with region-based 
> marshalling enabled, the cache loader isn't writing the region Fqn as 
> the leading part of the stream. That might be by design, as its OK if 
> we're *sure* the correct CL will always be assigned to the thread before 
> *any* attempt is made to read from the persistent store.
> 
> It's breaking down though in the FileCacheLoader.doUnmarshall call, 
> which is calling into the marshaller and letting it decide whether 
> region-based marshalling is in effect. The marshaller thinks it is, and 
> tries to unmarshall a leading region Fqn. This fails.
> 
> Here's a stack trace showing a failed read from the persistent store. 
> Read is occuring in preparation for a write, but it's the read that is 
> failing:
> 
> 2008-04-20 01:06:27,996 ERROR 
> [org.jboss.web.tomcat.service.session.JBossCacheManager] 
> (ContainerBackgroundProcessor[StandardEngine[jboss.web]]) 
> processExpires(): failed removing unloaded session 0Fm8CDBXTJp40M0Wfvjw6Q__
> java.lang.ClassCastException: java.util.HashMap
>     at 
> org.jboss.cache.marshall.CacheMarshaller200.objectFromObjectStreamRegionBased(CacheMarshaller200.java:175) 
> 
>     at 
> org.jboss.cache.marshall.CacheMarshaller200.objectFromObjectStream(CacheMarshaller200.java:115) 
> 
>     at 
> org.jboss.cache.marshall.VersionAwareMarshaller.objectFromObjectStream(VersionAwareMarshaller.java:324) 
> 
>     at 
> org.jboss.cache.loader.FileCacheLoader.doUnmarshall(FileCacheLoader.java:473) 
> 
>     at 
> org.jboss.cache.loader.AbstractCacheLoader.regionAwareUnmarshall(AbstractCacheLoader.java:221) 
> 
>     at 
> org.jboss.cache.loader.FileCacheLoader.loadAttributes(FileCacheLoader.java:426) 
> 
>     at org.jboss.cache.loader.FileCacheLoader.put(FileCacheLoader.java:247)
>     at org.jboss.cache.loader.FileCacheLoader.put(FileCacheLoader.java:238)
>     at 
> org.jboss.cache.interceptors.PassivationInterceptor.handleEvictMethod(PassivationInterceptor.java:53) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:126) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:58) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.PessimisticLockInterceptor.handleEvictMethod(PessimisticLockInterceptor.java:341) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:126) 
> 
>     at 
> org.jboss.cache.interceptors.PessimisticLockInterceptor.invoke(PessimisticLockInterceptor.java:81) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:58) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:58) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.TxInterceptor.handleNonTxMethod(TxInterceptor.java:456) 
> 
>     at 
> org.jboss.cache.interceptors.TxInterceptor.handleEvictMethod(TxInterceptor.java:200) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:126) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.CacheMgmtInterceptor.handleEvictMethod(CacheMgmtInterceptor.java:64) 
> 
>     at 
> org.jboss.cache.interceptors.MethodDispacherInterceptor.invoke(MethodDispacherInterceptor.java:126) 
> 
>     at 
> org.jboss.cache.interceptors.Interceptor.nextInterceptor(Interceptor.java:111) 
> 
>     at 
> org.jboss.cache.interceptors.InvocationContextInterceptor.invoke(InvocationContextInterceptor.java:73) 
> 
>     at 
> org.jboss.cache.invocation.AbstractInvocationDelegate.invoke(AbstractInvocationDelegate.java:123) 
> 
>     at 
> org.jboss.cache.invocation.AbstractInvocationDelegate.invoke(AbstractInvocationDelegate.java:64) 
> 
>     at 
> org.jboss.cache.invocation.CacheInvocationDelegate.evict(CacheInvocationDelegate.java:380) 
> 
>     at 
> org.jboss.cache.invocation.CacheInvocationDelegate.evictChildren(CacheInvocationDelegate.java:355) 
> 
>     at 
> org.jboss.cache.invocation.CacheInvocationDelegate.evict(CacheInvocationDelegate.java:340) 
> 
>     at 
> org.jboss.web.tomcat.service.session.JBossCacheWrapper.evictSubtree(JBossCacheWrapper.java:273) 
> 
>     at 
> org.jboss.web.tomcat.service.session.JBossCacheService.evictSession(JBossCacheService.java:388) 
> 
>     at 
> org.jboss.web.tomcat.service.session.JBossCacheManager.processUnloadedSessionPassivation(JBossCacheManager.java:1795) 
> 
>     at 
> org.jboss.web.tomcat.service.session.JBossCacheManager.processExpires(JBossCacheManager.java:1554) 
> 
>     at 
> org.jboss.web.tomcat.service.session.JBossManager.backgroundProcess(JBossManager.java:895) 
> 
>     at 
> org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1316) 
> 
>     at 
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601) 
> 
>     at 
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610) 
> 
>     at 
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610) 
> 
>     at 
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590) 
> 
>     at java.lang.Thread.run(Thread.java:595)
> 

-- 
Brian Stansberry
Lead, AS Clustering
JBoss, a division of Red Hat
brian.stansberry at redhat.com