Use LongAdder instead of an atomic long

LongAdder has better performance under contention,
use it for tracking counter.

Change-Id: If32e17a8e16b2a1418c744a54aaa84e8479f3852
Signed-off-by: Robert Varga <rovarga@cisco.com>

diff --git a/common/util/src/main/java/org/opendaylight/yangtools/util/concurrent/CountingRejectedExecutionHandler.java b/common/util/src/main/java/org/opendaylight/yangtools/util/concurrent/CountingRejectedExecutionHandler.java
index 89c8e3786689701f8b3d8aa842388fd8aa2afe4b..8fd45dc310ac0bafc80fce37a3b1f675f8bba182 100644 (file)
--- a/common/util/src/main/java/org/opendaylight/yangtools/util/concurrent/CountingRejectedExecutionHandler.java
+++ b/common/util/src/main/java/org/opendaylight/yangtools/util/concurrent/CountingRejectedExecutionHandler.java
@@ -11,7 +11,7 @@ package org.opendaylight.yangtools.util.concurrent;
 import com.google.common.base.Preconditions;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.atomic.AtomicLongFieldUpdater;
+import java.util.concurrent.atomic.LongAdder;
 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
 
 /**
@@ -21,10 +21,8 @@ import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  * @author Thomas Pantelis
  */
 public class CountingRejectedExecutionHandler implements RejectedExecutionHandler {
-    private static final AtomicLongFieldUpdater<CountingRejectedExecutionHandler> COUNTER_UPDATER =
-            AtomicLongFieldUpdater.newUpdater(CountingRejectedExecutionHandler.class, "rejectedTaskCounter");
+    private final LongAdder rejectedTaskCounter = new LongAdder();
     private final RejectedExecutionHandler delegate;
-    private volatile long rejectedTaskCounter;
 
     /**
      * Constructor.
@@ -37,15 +35,15 @@ public class CountingRejectedExecutionHandler implements RejectedExecutionHandle
 
     @Override
     public void rejectedExecution( final Runnable task, final ThreadPoolExecutor executor ) {
-        COUNTER_UPDATER.incrementAndGet(this);
-        delegate.rejectedExecution( task, executor );
+        rejectedTaskCounter.increment();
+        delegate.rejectedExecution(task, executor);
     }
 
     /**
      * Returns the rejected task count.
      */
     public long getRejectedTaskCount() {
-        return rejectedTaskCounter;
+        return rejectedTaskCounter.sum();
     }
 
     /**
@@ -54,14 +52,14 @@ public class CountingRejectedExecutionHandler implements RejectedExecutionHandle
      * the task is discarded.
      */
     public static CountingRejectedExecutionHandler newCallerRunsPolicy() {
-        return new CountingRejectedExecutionHandler( new ThreadPoolExecutor.CallerRunsPolicy() );
+        return new CountingRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
     }
 
     /**
      * Returns a counting handler for rejected tasks that throws a RejectedExecutionException.
      */
     public static CountingRejectedExecutionHandler newAbortPolicy() {
-        return new CountingRejectedExecutionHandler( new ThreadPoolExecutor.AbortPolicy() );
+        return new CountingRejectedExecutionHandler(new ThreadPoolExecutor.AbortPolicy());
     }
 
     /**
@@ -69,6 +67,6 @@ public class CountingRejectedExecutionHandler implements RejectedExecutionHandle
      * {@link ThreadPoolExecutor}'s backing queue until it can add the task to the queue.
      */
     public static CountingRejectedExecutionHandler newCallerWaitsPolicy() {
-        return new CountingRejectedExecutionHandler( ExecutorServiceUtil.waitInQueueExecutionHandler() );
+        return new CountingRejectedExecutionHandler(ExecutorServiceUtil.waitInQueueExecutionHandler());
     }
 }