Threads parked waiting for EJB instance causing slowness in application in EAP 6

Issue

Lot of threads found in TIMED_WAIT parked state waiting for EJB instance to get free. Below is observed in thread stack trace from thread dumps:

   java.lang.Thread.State: TIMED_WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x00000007026c4098> (a java.util.concurrent.Semaphore$FairSync)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:196)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos(AbstractQueuedSynchronizer.java:1011)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireSharedNanos(AbstractQueuedSynchronizer.java:1303)
    at java.util.concurrent.Semaphore.tryAcquire(Semaphore.java:383)
    at org.jboss.as.ejb3.pool.strictmax.StrictMaxPool.get(StrictMaxPool.java:107)
    at org.jboss.as.ejb3.component.pool.PooledInstanceInterceptor.processInvocation(PooledInstanceInterceptor.java:47)