I am getting a similar deadlock as the one in the cloned issue. We are using following dependencies:
<dependency>
<groupId>org.drools</groupId>
<artifactId>drools-templates</artifactId>
<version>$

{runtime.version}</version>
</dependency>
<dependency>
<groupId>org.kie</groupId>
<artifactId>kie-api</artifactId>
<version>${runtime.version}
</version>
</dependency>
<dependency>
<groupId>org.drools</groupId>
<artifactId>drools-core</artifactId>
<version>${runtime.version}

</version>
</dependency>
<dependency>
<groupId>org.drools</groupId>
<artifactId>drools-compiler</artifactId>
<version>${runtime.version}
</version>
</dependency>
runtime.version = 6.5.0-Final
I have around 50 off threads stuck in a deadlock. 49 of them are having following stack trace:
"THREAD-4" #124 prio=5 os_prio=0 tid=0x00000000015fc800 nid=0x3a5d waiting on condition [0x00007fc773e7b000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
parking to wait for <0x000000074d189818> (a java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared(AbstractQueuedSynchronizer.java:967)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(AbstractQueuedSynchronizer.java:1283)
at java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(ReentrantReadWriteLock.java:727)
at org.drools.core.impl.KnowledgeBaseImpl.readLock(KnowledgeBaseImpl.java:703)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulSession(KnowledgeBaseImpl.java:1434)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulSession(KnowledgeBaseImpl.java:1422)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulKnowledgeSession(KnowledgeBaseImpl.java:308)
at org.drools.core.impl.KnowledgeBaseImpl.newKieSession(KnowledgeBaseImpl.java:385)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:693)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:629)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:611)
And one of them is stuck in the following stack trace:
"THREAD-4" #124 prio=5 os_prio=0 tid=0x00000000015fc800 nid=0x3a5d waiting on condition [0x00007fc773e7b000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
parking to wait for <0x000000074d189818> (a java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared(AbstractQueuedSynchronizer.java:967)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(AbstractQueuedSynchronizer.java:1283)
at java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(ReentrantReadWriteLock.java:727)
at org.drools.core.impl.KnowledgeBaseImpl.readLock(KnowledgeBaseImpl.java:703)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulSession(KnowledgeBaseImpl.java:1434)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulSession(KnowledgeBaseImpl.java:1422)
at org.drools.core.impl.KnowledgeBaseImpl.newStatefulKnowledgeSession(KnowledgeBaseImpl.java:308)
at org.drools.core.impl.KnowledgeBaseImpl.newKieSession(KnowledgeBaseImpl.java:385)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:693)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:629)
at org.drools.compiler.kie.builder.impl.KieContainerImpl.newKieSession(KieContainerImpl.java:611)
Please help us out in fixing this. Its a production system serving millions of users.
PS: This is was reproduced under a medium load where we create 50 stateful sessions in parallel and also some rule were also getting added in the KieContainer at the same time.