Performance Ehcache过期和死锁

我使用的是Hibernate4.2.20和Ehcache2.6.6

我有2个实体和一个spring数据存储库，如下所示：

@Entity
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
@Cache(region = "branch", usage = CacheConcurrencyStrategy.TRANSACTIONAL)
public abstract class AbstractBranch{
 .....
}

@Entity
@Table(name = "branch")
public class Branch extends AbstractBranch {
}

public interface BranchRepository extends BaseRepository<Branch, UUID> {
     @QueryHints({ @QueryHint(name = "org.hibernate.cacheable", value = "true"), @QueryHint(name = "org.hibernate.cacheRegion", value = "branch") })
     Branch findByBranchId(String branchId);
}

我开始出现超时/死锁异常。看到stracktrace了吗

TimeoutManage I   WTRN0124I: When the timeout occurred the thread with which the transaction is, or was most recently, associated was Thread[WebContainer : 96,5,main]. The stack trace of this thread when the timeout occurred was: 
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.park(LockSupport.java:197)
java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:845)
java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared(AbstractQueuedSynchronizer.java:975)
java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(AbstractQueuedSynchronizer.java:1293)
java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(ReentrantReadWriteLock.java:742)
net.sf.ehcache.store.FrontEndCacheTier.containsKeyInMemory(FrontEndCacheTier.java:483)
net.sf.ehcache.transaction.AbstractTransactionStore.containsKeyInMemory(AbstractTransactionStore.java:187)
net.sf.ehcache.transaction.AbstractTransactionStore.containsKeyInMemory(AbstractTransactionStore.java:187)
net.sf.ehcache.Cache.searchInStoreWithStats(Cache.java:1941)
net.sf.ehcache.Cache.get(Cache.java:1584)
org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion.get(EhcacheGeneralDataRegion.java:74)
org.hibernate.cache.ehcache.internal.regions.EhcacheQueryResultsRegion.get(EhcacheQueryResultsRegion.java:39)
org.hibernate.cache.internal.StandardQueryCache.getCachedResults(StandardQueryCache.java:201)
org.hibernate.cache.internal.StandardQueryCache.get(StandardQueryCache.java:140)
org.hibernate.loader.Loader.getResultFromQueryCache(Loader.java:2477)
org.hibernate.loader.Loader.listUsingQueryCache(Loader.java:2385)
org.hibernate.loader.Loader.list(Loader.java:2358)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:495)
org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:357)
org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:198)
org.hibernate.internal.SessionImpl.list(SessionImpl.java:1230)
org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:287)
org.hibernate.ejb.criteria.CriteriaQueryCompiler$3.getSingleResult(CriteriaQueryCompiler.java:258)
org.springframework.data.jpa.repository.query.JpaQueryExecution$SingleEntityExecution.doExecute(JpaQueryExecution.java:206)
org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:78)
org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:100)
org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:91)
org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:413)
org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:391)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodIntercceptor.invoke(CrudMethodMetadataPostProcessor.java:122)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
com.sun.proxy.$Proxy125.findByBranchId(Unknown Source)

我已经发布了一个线程转储在 这显示了5个阻塞线程

---

有人知道如何防止这种情况发生吗？

根据EhCache文档，由于您在EhCache.xml中指定的XA事务模式，这些可能是“正常”超时异常

这种XA模式将在更新、删除或添加期间使用写锁。。。对于并发访问，这些锁会导致一些线程阻塞并出现死锁。最终，死锁线程超时（并引发异常），以避免陷入死锁状态

---

查看此页面，常见问题解答部分在“为什么某些线程经常超时并引发异常？”的问题下明确提到了这一点。

可以通过在LocalTransactionStore:put中设置断点来重现此问题。如果缓存已过期，则触发第一个请求，执行将在put中停止。然后触发第二个请求，该请求将到达remove并等待原始锁。重新启动第一个线程，就会出现死锁

以下是我认为它锁定的原因：

线程1：（堆栈锁定）

ReentrantReadWriteLock$NonfairSync（AbstractQueuedSynchronizer）。doAcquireShared（int）行：955
ReentrantReadWriteLock$NonfairSync（AbstractQueuedSynchronizer）。acquireShared（int）行：1282
ReentrantReadWriteLock$ReadLock.lock（）行：731
MemoryOnlyStore（前端缓存层）.isPinned（对象）行：111
LocalTransactionStore.put（元素）行：226
JtaLocalTransactionStore.put（元素）行：275

private void-doAcquireShared（int-arg）->int r=tryAcquireShared（arg）；->else if（当前==getExclusiveOwnerThread（））

线程2： （堆栈设置独占所有者线程）

java.util.concurrent.locks.AbstractOwnableSynchronizer.setExclusiveOwnerThread（AbstractOwnableSynchronizer.java:56）
java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryAcquire（ReentrantReadWriteLock.java:411）
java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireNanos（AbstractQueuedSynchronizer.java:1245）
java.util.concurrent.locks.ReentrantReadWriteLock$WriteLock.tryLock（ReentrantReadWriteLock.java:1115）
net.sf.ehcache.concurrent.ReadWriteLockSync.tryLock（ReadWriteLockSync.java:57）
net.sf.ehcache.Cache.tryremoviely（Cache.java:2103）
net.sf.ehcache.Cache.searchInStoreWithStats（Cache.java:1963）
net.sf.ehcache.Cache.get（Cache.java:1584）
org.hibernate.cache.ehcache.internal.strategy.TransactionalHcacheEntityRegionaccessStrategy.putFromLoad（TransactionalHcacheEntityRegionaccessStrategy.java:122）
org.hibernate.cache.ehcache.internal.nonstop.nonspawareentityregionaccessstrategy.putFromLoad（nonspawareentityregionaccessstrategy.java:195）

（堆栈锁定）

Unsafe.park（布尔值，长）行：不可用[本机方法]
锁支架。帕克纳（物体，长）线：226
ReentrantLock$NonfairSync（AbstractQueuedSynchronizer）.doAcquireNanos（int，long）行：929
ReentrantLock$NonfairSync（AbstractQueuedSynchronizer）.tryAcquireNanos（int，long）行：1245
ReentrantLock.tryLock（长，时间单位）行：445
ReadCommittedSoftLockImpl.tryLock（长）行：85
LocalTransactionStore.remove（对象）行：467
JtaLocalTransactionStore.remove（对象）行：371
Cache.removeInternal（对象，布尔，布尔，布尔，布尔）行：2334
Cache.tryremoviely立即（对象，布尔值）行：2117

Cache.searchInStoreWithStats（对象）行：1963
Cache.get（对象）行：1584

TransactionalCacheEntityRegionaccessStrategy.putFromLoad（对象，对象，长，对象，布尔值）行：122

第二个线程集ExclusiveOwnerThread作为：tryacquirenos->tryAcquire（arg）的一部分，然后作为：tryacquirenos->doacquirenos（arg，nanotimeout）的一部分停驻，因此，它不注册读或写锁，但将锁留给独占所有者集

从这一点开始，第一个线程中对ReadLock.lock的任何调用都将停止，因为tryAcquireShared失败，因为current==getExclusiveOwnerThread（）为false，从而导致死锁

现在的问题是：为什么ReadLock.lock（）会离开独占所有者线程集

更新：扩展堆栈我意识到事件发生在net.sf.ehcache.Cache的不同部分，并使用不同的类：

Cache.tryremoviely立即（Cache.java:2103）->ReadWriteLockSync.tryLock（ReadWriteLockSync.java:57）

Cache.tryremovieimmediately（Object，boolean）行：2117->（…）->ReentrantLock.tryLock（long，TimeUnit）

第一个设置独占所有者线程，并在tryAcquire中返回true

ReentrantReadWriteLock$Sync.tryAcquire

protected final boolean tryAcquire（整数获取）{
/*
*演练：
*1.如果读取计数非零或写入计数非零
*而所有者是另一个线程，失败。
*2.如果计数将饱和，则失败。（这只能
*如果计数已非零，则发生。）
*3.否则，如果
*它要么是可重入获取，要么是
*队列策略允许。如果允许，请更新状态
*并设置所有者。
*/
线程当前=Thread.currentThread（）；
int c=getState（）；
int w=排他性账户（c）；
如果（c！=0）{
//（注意：如果c！=0且w=0，则共享计数！=0）
如果（w==0 | | current！=getExclusiveOwnerThread（））
返回false；
if（w+独家帐户（收购）>最大计数）
抛出新的
branchRepository.findByBranchId(...).

TimeoutManage I   WTRN0124I: When the timeout occurred the thread with which the transaction is, or was most recently, associated was Thread[WebContainer : 96,5,main]. The stack trace of this thread when the timeout occurred was: 
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.park(LockSupport.java:197)
java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:845)
java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared(AbstractQueuedSynchronizer.java:975)
java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(AbstractQueuedSynchronizer.java:1293)
java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(ReentrantReadWriteLock.java:742)
net.sf.ehcache.store.FrontEndCacheTier.containsKeyInMemory(FrontEndCacheTier.java:483)
net.sf.ehcache.transaction.AbstractTransactionStore.containsKeyInMemory(AbstractTransactionStore.java:187)
net.sf.ehcache.transaction.AbstractTransactionStore.containsKeyInMemory(AbstractTransactionStore.java:187)
net.sf.ehcache.Cache.searchInStoreWithStats(Cache.java:1941)
net.sf.ehcache.Cache.get(Cache.java:1584)
org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion.get(EhcacheGeneralDataRegion.java:74)
org.hibernate.cache.ehcache.internal.regions.EhcacheQueryResultsRegion.get(EhcacheQueryResultsRegion.java:39)
org.hibernate.cache.internal.StandardQueryCache.getCachedResults(StandardQueryCache.java:201)
org.hibernate.cache.internal.StandardQueryCache.get(StandardQueryCache.java:140)
org.hibernate.loader.Loader.getResultFromQueryCache(Loader.java:2477)
org.hibernate.loader.Loader.listUsingQueryCache(Loader.java:2385)
org.hibernate.loader.Loader.list(Loader.java:2358)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:495)
org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:357)
org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:198)
org.hibernate.internal.SessionImpl.list(SessionImpl.java:1230)
org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:287)
org.hibernate.ejb.criteria.CriteriaQueryCompiler$3.getSingleResult(CriteriaQueryCompiler.java:258)
org.springframework.data.jpa.repository.query.JpaQueryExecution$SingleEntityExecution.doExecute(JpaQueryExecution.java:206)
org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:78)
org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:100)
org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:91)
org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:413)
org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:391)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodIntercceptor.invoke(CrudMethodMetadataPostProcessor.java:122)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
com.sun.proxy.$Proxy125.findByBranchId(Unknown Source)