BUG-1120: improve notification queue
[controller.git] / opendaylight / md-sal / sal-binding-broker / src / main / java / org / opendaylight / controller / sal / binding / codegen / impl / SingletonHolder.java
index a0bbb28d9e07624e23ad0afd094c347c27d2fce2..1ec4aa2d30bc9da7307891a41050bfc33e55642a 100644 (file)
  */
 package org.opendaylight.controller.sal.binding.codegen.impl;
 
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
 
 import javassist.ClassPool;
 
+import org.apache.commons.lang3.StringUtils;
 import org.opendaylight.controller.sal.binding.codegen.RuntimeCodeGenerator;
 import org.opendaylight.controller.sal.binding.spi.NotificationInvokerFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import com.google.common.util.concurrent.ForwardingBlockingQueue;
 import com.google.common.util.concurrent.ListeningExecutorService;
 import com.google.common.util.concurrent.MoreExecutors;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 
 public class SingletonHolder {
+    private static final Logger logger = LoggerFactory.getLogger(SingletonHolder.class);
 
-    public static final ClassPool CLASS_POOL = new ClassPool();
+    public static final ClassPool CLASS_POOL = ClassPool.getDefault();
     public static final org.opendaylight.controller.sal.binding.codegen.impl.RuntimeCodeGenerator RPC_GENERATOR_IMPL = new org.opendaylight.controller.sal.binding.codegen.impl.RuntimeCodeGenerator(
             CLASS_POOL);
     public static final RuntimeCodeGenerator RPC_GENERATOR = RPC_GENERATOR_IMPL;
     public static final NotificationInvokerFactory INVOKER_FACTORY = RPC_GENERATOR_IMPL.getInvokerFactory();
+
+    public static final int CORE_NOTIFICATION_THREADS = 4;
+    public static final int MAX_NOTIFICATION_THREADS = 32;
+    // block caller thread after MAX_NOTIFICATION_THREADS + MAX_NOTIFICATION_QUEUE_SIZE pending notifications
+    public static final int MAX_NOTIFICATION_QUEUE_SIZE = 1000;
+    public static final int NOTIFICATION_THREAD_LIFE = 15;
+    private static final String NOTIFICATION_QUEUE_SIZE_PROPERTY = "mdsal.notificationqueue.size";
+
     private static ListeningExecutorService NOTIFICATION_EXECUTOR = null;
     private static ListeningExecutorService COMMIT_EXECUTOR = null;
     private static ListeningExecutorService CHANGE_EVENT_EXECUTOR = null;
 
-    public static synchronized final ListeningExecutorService getDefaultNotificationExecutor() {
+    /**
+     * @deprecated This method is only used from configuration modules and thus callers of it
+     *             should use service injection to make the executor configurable.
+     */
+    @Deprecated
+    public static synchronized ListeningExecutorService getDefaultNotificationExecutor() {
+
         if (NOTIFICATION_EXECUTOR == null) {
-            NOTIFICATION_EXECUTOR = createNamedExecutor("md-sal-binding-notification-%d");
+            int queueSize = MAX_NOTIFICATION_QUEUE_SIZE;
+            String queueValue = System.getProperty(NOTIFICATION_QUEUE_SIZE_PROPERTY);
+            if (StringUtils.isNotBlank(queueValue)) {
+                try {
+                    queueSize = Integer.parseInt(queueValue);
+                    logger.trace("Queue size was set to {}", queueSize);
+                } catch (NumberFormatException e) {
+                    logger.warn("Cannot parse {} as set by {}, using default {}", queueValue,
+                            NOTIFICATION_QUEUE_SIZE_PROPERTY, queueSize);
+                }
+            }
+
+            // Overriding the queue:
+            // ThreadPoolExecutor would not create new threads if the queue is not full, thus adding
+            // occurs in RejectedExecutionHandler.
+            // This impl saturates threadpool first, then queue. When both are full caller will get blocked.
+            final BlockingQueue<Runnable> delegate = new LinkedBlockingQueue<>(queueSize);
+            final BlockingQueue<Runnable> queue = new ForwardingBlockingQueue<Runnable>() {
+                @Override
+                protected BlockingQueue<Runnable> delegate() {
+                    return delegate;
+                }
+
+                @Override
+                public boolean offer(final Runnable r) {
+                    // ThreadPoolExecutor will spawn a new thread after core size is reached only
+                    // if the queue.offer returns false.
+                    return false;
+                }
+            };
+
+            final ThreadFactory factory = new ThreadFactoryBuilder()
+            .setDaemon(true)
+            .setNameFormat("md-sal-binding-notification-%d")
+            .build();
+
+            final ThreadPoolExecutor executor = new ThreadPoolExecutor(CORE_NOTIFICATION_THREADS, MAX_NOTIFICATION_THREADS,
+                    NOTIFICATION_THREAD_LIFE, TimeUnit.SECONDS, queue, factory,
+                    new RejectedExecutionHandler() {
+                // if the max threads are met, then it will raise a rejectedExecution. We then push to the queue.
+                @Override
+                public void rejectedExecution(final Runnable r, final ThreadPoolExecutor executor) {
+                    try {
+                        executor.getQueue().put(r);
+                    } catch (InterruptedException e) {
+                        throw new RejectedExecutionException("Interrupted while waiting on the queue", e);
+                    }
+                }
+            });
+
+            NOTIFICATION_EXECUTOR = MoreExecutors.listeningDecorator(executor);
         }
+
         return NOTIFICATION_EXECUTOR;
     }
 
@@ -43,16 +119,16 @@ public class SingletonHolder {
      *             should use service injection to make the executor configurable.
      */
     @Deprecated
-    public static synchronized final ListeningExecutorService getDefaultCommitExecutor() {
+    public static synchronized ListeningExecutorService getDefaultCommitExecutor() {
         if (COMMIT_EXECUTOR == null) {
             ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("md-sal-binding-commit-%d").build();
-           /*
-            * FIXME: this used to be newCacheThreadPool(), but MD-SAL does not have transaction
-            *        ordering guarantees, which means that using a concurrent threadpool results
-            *        in application data being committed in random order, potentially resulting
-            *        in inconsistent data being present. Once proper primitives are introduced,
-            *        concurrency can be reintroduced.
-            */
+            /*
+             * FIXME: this used to be newCacheThreadPool(), but MD-SAL does not have transaction
+             *        ordering guarantees, which means that using a concurrent threadpool results
+             *        in application data being committed in random order, potentially resulting
+             *        in inconsistent data being present. Once proper primitives are introduced,
+             *        concurrency can be reintroduced.
+             */
             ExecutorService executor = Executors.newSingleThreadExecutor(factory);
             COMMIT_EXECUTOR = MoreExecutors.listeningDecorator(executor);
         }
@@ -60,12 +136,6 @@ public class SingletonHolder {
         return COMMIT_EXECUTOR;
     }
 
-    private static ListeningExecutorService createNamedExecutor(String format) {
-        ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat(format).build();
-        ExecutorService executor = Executors.newCachedThreadPool(factory);
-        return MoreExecutors.listeningDecorator(executor);
-    }
-
     public static ExecutorService getDefaultChangeEventExecutor() {
         if (CHANGE_EVENT_EXECUTOR == null) {
             ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("md-sal-binding-change-%d").build();