The synchronized block in this method has been identified as a potential
bottleneck.

 /** The subpools */
 private final Map pools = new HashMap();

 /** Track by connection by tx values */
 private final Map trackByTxPools = new ConcurrentReaderHashMap();


 /**
 * Determine the correct pool for this request,
 * creates a new one when necessary
 *
 * @param key the key to the pool
 * @param subject the subject of the pool
 * @param cri the connection request info
 * @return the pool
 * @throws ResourceException for any error
 */
 private InternalManagedConnectionPool getPool(Object key, Subject subject, ConnectionRequestInfo cri)
 throws ResourceException
 {
 InternalManagedConnectionPool mcp = null;
 synchronized (pools)
 {
 mcp = (InternalManagedConnectionPool) pools.get(key);
 if (mcp == null)
 {
 mcp = new InternalManagedConnectionPool(mcf, clf, subject, cri, poolParams, log);
 pools.put(key, mcp);
 TransactionManager tm = getTransactionManager();
 if (tm != null)
 trackByTxPools.put(key, new TransactionLocal(tm));
 }
 }
 return mcp;
 }