Make connection Validation (at ConnectionValidator) outside of lock ------------------------------------------------------------------- Key: JBJCA-1403 URL: https://issues.redhat.com/browse/JBJCA-1403 Project: IronJacamar Issue Type: Enhancement Reporter: Flavia Rainone Assignee: Flavia Rainone Priority: Major As can be seen in the following stack trace, connection validation inside the connection validator lock might lock the entire prefill of other pools: {code} "default task-1122" #4743 prio=5 os_prio=0 tid=0x000000000929f800 nid=0x12067 waiting for monitor entry [0x00007fe6c7305000] java.lang.Thread.State: BLOCKED (on object monitor) at org.jboss.jca.core.connectionmanager.pool.AbstractPool.getManagedConnectionPool(AbstractPool.java:299) - waiting to lock <0x0000000083be8028> (a org.jboss.jca.core.connectionmanager.pool.strategy.PoolBySubject) at org.jboss.jca.core.connectionmanager.pool.AbstractPool.getConnection(AbstractPool.java:596) at org.jboss.jca.core.connectionmanager.AbstractConnectionManager.getManagedConnection(AbstractConnectionManager.java:624) at org.jboss.jca.core.connectionmanager.tx.TxConnectionManagerImpl.getManagedConnection(TxConnectionManagerImpl.java:440) at org.jboss.jca.core.connectionmanager.AbstractConnectionManager.allocateConnection(AbstractConnectionManager.java:789) at org.jboss.jca.adapters.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:151) at org.jboss.as.connector.subsystems.datasources.WildFlyDataSource.getConnection(WildFlyDataSource.java:64) ... "default task-1144" #4839 prio=5 os_prio=0 tid=0x000000000ccca800 nid=0x12718 waiting on condition [0x00007fe6cc532000] java.lang.Thread.State: WAITING (parking) at sun.misc.Unsafe.park(Native Method) - parking to wait for <0x000000008082b8f8> (a java.util.concurrent.locks.ReentrantLock$FairSync) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870) at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199) at java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:224) at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285) at org.jboss.jca.core.connectionmanager.pool.validator.ConnectionValidator.internalRegisterPool(ConnectionValidator.java:185) at org.jboss.jca.core.connectionmanager.pool.validator.ConnectionValidator.registerPool(ConnectionValidator.java:167) at org.jboss.jca.core.connectionmanager.pool.mcp.SemaphoreConcurrentLinkedDequeManagedConnectionPool.initialize(SemaphoreConcurrentLinkedDequeManagedConnectionPool.java:196) at org.jboss.jca.core.connectionmanager.pool.mcp.ManagedConnectionPoolFactory.init(ManagedConnectionPoolFactory.java:191) at org.jboss.jca.core.connectionmanager.pool.mcp.ManagedConnectionPoolFactory.create(ManagedConnectionPoolFactory.java:173) at org.jboss.jca.core.connectionmanager.pool.AbstractPool.getManagedConnectionPool(AbstractPool.java:306) - locked <0x0000000083be8028> (a org.jboss.jca.core.connectionmanager.pool.strategy.PoolBySubject) at org.jboss.jca.core.connectionmanager.pool.AbstractPool.getConnection(AbstractPool.java:596) at org.jboss.jca.core.connectionmanager.AbstractConnectionManager.getManagedConnection(AbstractConnectionManager.java:624) at org.jboss.jca.core.connectionmanager.tx.TxConnectionManagerImpl.getManagedConnection(TxConnectionManagerImpl.java:440) at org.jboss.jca.core.connectionmanager.AbstractConnectionManager.allocateConnection(AbstractConnectionManager.java:789) at org.jboss.jca.adapters.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:151) at org.jboss.as.connector.subsystems.datasources.WildFlyDataSource.getConnection(WildFlyDataSource.java:64) {code} The reason for this is that a new pool must be registered, and currently this operation is being blocked by connection validation. If connection validation is slow, this could compromise other threads creating pools and connections as shown in the example.