Ehcache 2.9.0中的Ehcache死锁

Question

我们有应用程序使用EHCache2.9.0。最近，我们每周观察到一次与ehcache Get/Put操作相关的死锁，一旦清除缓存，问题就消失了。

我们在缓存get操作期间观察RandomAccessFile上的锁，在put操作期间观察ReentrantReadWriteLock上的锁。

请ehcache专家就可能出现的问题提出见解？

“http938”#25950守护进程prio=5 os_prio=0 tid=0x0000000002614000 nid=0x5A64在条件[0x00007FCD36965000]java.lang.thread.state:waiting（parking）在sun.misc.unsafe.park（本机方法）-在java.util.concurrent.locks.locks.locks.locksupport.park（edsynchronizer.java:836)在java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared（AbstractQueuedSynchronizer.java:967)在java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared（AbstractQueuedSynchronizer.java:1283)在java.util.concurrent.clocks.ReentrantReadWriteLock$readLock.lock 248）在net.sf.ehcache.store.cacheStore$1.evicat(cacheStore.java:99）在net.sf.ehcache.store.cacheStore$1.在net.sf.ehcache.store.cachingtier.onheapcachingtier$1.在net.sf.ehcache.store.cachingtier.onheapcachingtier.java:86)在net.sf.ehcache.store.cachingtier.countbasedbackend$1.在net.sf.ehcache.store.countbasedbackend$1.在removeandnotify(concurrenthashmap.java:2647)在net.sf.ehcache.store.cachingtier.countbasedbackend.remove(countbasedbackend.java:115)在net.sf.ehcache.store.cachingtier.onheapcachingtier.remove(onheapcachingtier.java:206)在net.sf.ehcache.store.cachestore.java:134)在net.sf.ehcache.java:134)在net.sf.ehcache.cache.put（在net.sf.ehcache.cache.put（cache.java:1491)在org.springframework.cache.ehcache.cache.put（ehcacheCache.java:82)在org.springframework.cache.interceptor.abstractCacheInvoker.doput（abstractCacheInvoker.java:82)在org.springframework.cache.interceptor.cacheaspectsupport.apply(cacheaspectsupport.java:651)在org.springframework.cache.interceptor.cacheaspectsupport.execute(cacheaspectsupport.java:358)在org.springframework.cache.interceptor.cacheaspectsupport.execute(cacheaspectsupport.java:299)在invocation.java:179)在org.springframework.aop.framework.cglibaopproxy$DynamicAdvisedInterceptor.Intercept(cglibaopProxy.java:653)

“http927”#25855守护进程prio=5 os_prio=0 tid=0x00007fce685c9000 nid=0x4fb6等待监视器条目[0x00007fcd359e8000]java.lang.thread.state:在net.sf.ehcache.store.disk.diskStorageFactory.read(diskStorageFactory.read)(diskStorageFactory.java:362)上被阻止（在对象监视器上）-在net.sf.ehcache.store.diskStorageFactory.readeve上等待锁定java:864)在net.sf.ehcache.store.disk.segment.decode（segment.java:171)在net.sf.ehcache.store.disk.segment.remove（segment.java:644)在net.sf.ehcache.store.disk.disk.segment.remove（diskstore.java:625)在net.sf.ehcache.store.cachestore.remove（diskstore.java:236)在2162）在net.sf.ehcache.cache.get（cache.java:1739)在org.springframework.cache.ehcache.cache.get（ehcacheCache.java:65)在org.springframework.cache.interceptor.abstractCacheInvoker.doget（abstractCacheInvoker.java:68)在org.springframework.cache.interceptor.cacheaspectsupport.findincaches（cacheaspectsupport.java:461)在org.springframework.cache.interceptor.cacheaspectsupport.findcacheditem（cacheaspectsupport.java:432)在org.springframework.cache.interceptor.cacheaspectsupport.java:432)在在org.springframework.aop.framework.reflectiveMethodInvocation.proce(reflectiveMethodInvocation.java:179)在org.springframework.aop.framework.cglibaopproxy$DynamicAdvisedInterceptor.Intercept(cglibaopProxy.java:653)

线程HTTP762在java.io.randomaccessfile.readwill(randomaccessfile.java:416)的0x00000005CBDFB538上拥有监视器锁--在org.springframework.cache.ehcache.ehcacheCache.put(EhcacheCache.java:82)上锁定[0x00000005CBDFB538]（一个java.io.randomaccessfile）

Answer 1

我可能遗漏了一些东西，但在您显示的线程转储中没有看到任何死锁。只有两个线程在等待不同的事情，但不持有另一个线程。

第一次尝试必须在PUT上逐出一个值。

第二个线程通知一个条目已过期，并且正在从磁盘存储中删除。