[POOL-340] borrowObject is stuck, if create fails

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.4, 2.4.1, 2.4.2, 2.4.3, 2.5.0
• Fix Version/s: 2.6.1
• Assignee: Mark Struberg
• Reporter: Pavel Kolesov
• Created: 18/Apr/18 09:03
• Updated: 27/Oct/18 19:44
• Resolved: 27/Oct/18 19:44

Description

After changes in 2.4.3 there is a high chance of a scenario, in which borrowObject waits infinitely, if create fails or no one calls a create.

   java.lang.Thread.State: WAITING (parking)
        at sun.misc.Unsafe.park(Native Method)
        - parking to wait for  <0x0000000083cfd978> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
        at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
        at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
        at org.apache.commons.pool2.impl.LinkedBlockingDeque.takeFirst(LinkedBlockingDeque.java:583)
        at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:442)
        at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:363)

If pool is exhausted, when borrowObject tries to get idle object, it waits for new object to be created.
If all objects are returned to pool invalid and destroyed, and it is impossible to create a new one, borrowObject will not return.
Even if afterwards it is becomes possible to crate a new object but no one creates it, borrowObject will not return either.

Issue Links

• is related to: POOL-347 borrowObject waits for maxWaitMillis over in pool full