Merge branch '2.3.x' into dev

* 2.3.x:
  Update release version
  [maven-release-plugin] prepare for next development iteration
  [maven-release-plugin] prepare release HikariCP-2.3.7
  Update change log.
  Escew fastpath if there are pending threads waiting to avoid starvation of those threads.

CHANGES

@@ -10,6 +10,21 @@ Changes in 2.4.0
 
  * Deprecated HikariDataSource.shutdown() in favor of close().
 
+Changes in 2.3.7
+
+ * Try harder at resolving the driver by various means when both driverClassName and jdbcUrl
+   have been specified.
+
+ * Allow a specifically set DataSource instance to override other settings such as jdbcUrl,
+   dataSourceClassName, or driverClassName.
+ 
+ * Fixed issue where, in the case of a driver-based configuration (jdbcUrl), we were not
+   initialising the network timeout Executor.
+
+ * Fixed race condition uncovered during load-testing in which the connections in the pool
+   can spike to the maximum pool size when many connections reach their maxLifetime at the
+   same time.
+
 Changes in 2.3.6
 
  * Allow explicit definition of driverClassName to override DriverManager.getDriver(url)

src/main/java/com/zaxxer/hikari/util/ConcurrentBag.java

@@ -90,16 +90,18 @@ public class ConcurrentBag<T extends IConcurrentBagEntry> implements AutoCloseab
    @SuppressWarnings("unchecked")
    public T borrow(long timeout, final TimeUnit timeUnit) throws InterruptedException
    {
-      // Try the thread-local list first
-      final ArrayList<WeakReference<IConcurrentBagEntry>> list = threadList.get();
-      if (list == null) {
-         threadList.set(new ArrayList<WeakReference<IConcurrentBagEntry>>(16));
-      }
-      else {
-         for (int i = list.size() - 1; i >= 0; i--) {
-            final IConcurrentBagEntry bagEntry = list.remove(i).get();
-            if (bagEntry != null && bagEntry.state().compareAndSet(STATE_NOT_IN_USE, STATE_IN_USE)) {
-               return (T) bagEntry;
+      if (!synchronizer.hasQueuedThreads()) {
+         // Try the thread-local list first
+         final ArrayList<WeakReference<IConcurrentBagEntry>> list = threadList.get();
+         if (list == null) {
+            threadList.set(new ArrayList<WeakReference<IConcurrentBagEntry>>(16));
+         }
+         else {
+            for (int i = list.size() - 1; i >= 0; i--) {
+               final IConcurrentBagEntry bagEntry = list.remove(i).get();
+               if (bagEntry != null && bagEntry.state().compareAndSet(STATE_NOT_IN_USE, STATE_IN_USE)) {
+                  return (T) bagEntry;
+               }
             }
          }
       }