opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/codegen/impl/SingletonHolder.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.sal.binding.codegen.impl;
   9
  10 import com.google.common.util.concurrent.ListeningExecutorService;
  11 import com.google.common.util.concurrent.MoreExecutors;
  12 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  13 import javassist.ClassPool;
  14 import org.opendaylight.controller.sal.binding.codegen.RuntimeCodeGenerator;
  15 import org.opendaylight.controller.sal.binding.spi.NotificationInvokerFactory;
  16
  17 import java.util.concurrent.BlockingQueue;
  18 import java.util.concurrent.ExecutorService;
  19 import java.util.concurrent.Executors;
  20 import java.util.concurrent.LinkedBlockingQueue;
  21 import java.util.concurrent.RejectedExecutionHandler;
  22 import java.util.concurrent.ThreadFactory;
  23 import java.util.concurrent.ThreadPoolExecutor;
  24 import java.util.concurrent.TimeUnit;
  25
  26 public class SingletonHolder {
  27
  28     public static final ClassPool CLASS_POOL = ClassPool.getDefault();
  29     public static final org.opendaylight.controller.sal.binding.codegen.impl.RuntimeCodeGenerator RPC_GENERATOR_IMPL = new org.opendaylight.controller.sal.binding.codegen.impl.RuntimeCodeGenerator(
  30             CLASS_POOL);
  31     public static final RuntimeCodeGenerator RPC_GENERATOR = RPC_GENERATOR_IMPL;
  32     public static final NotificationInvokerFactory INVOKER_FACTORY = RPC_GENERATOR_IMPL.getInvokerFactory();
  33
  34     public static final int CORE_NOTIFICATION_THREADS = 4;
  35     public static final int MAX_NOTIFICATION_THREADS = 32;
  36     // block caller thread after MAX_NOTIFICATION_THREADS + MAX_NOTIFICATION_QUEUE_SIZE pending notifications
  37     public static final int MAX_NOTIFICATION_QUEUE_SIZE = 10;
  38     public static final int NOTIFICATION_THREAD_LIFE = 15;
  39
  40     private static ListeningExecutorService NOTIFICATION_EXECUTOR = null;
  41     private static ListeningExecutorService COMMIT_EXECUTOR = null;
  42     private static ListeningExecutorService CHANGE_EVENT_EXECUTOR = null;
  43
  44     /**
  45      * @deprecated This method is only used from configuration modules and thus callers of it
  46      *             should use service injection to make the executor configurable.
  47      */
  48     @Deprecated
  49     public static synchronized final ListeningExecutorService getDefaultNotificationExecutor() {
  50
  51         if (NOTIFICATION_EXECUTOR == null) {
  52             // Overriding the queue:
  53             // ThreadPoolExecutor would not create new threads if the queue is not full, thus adding
  54             // occurs in RejectedExecutionHandler.
  55             // This impl saturates threadpool first, then queue. When both are full caller will get blocked.
  56             BlockingQueue<Runnable> queue = new LinkedBlockingQueue<Runnable>(MAX_NOTIFICATION_QUEUE_SIZE) {
  57                 @Override
  58                 public boolean offer(Runnable r) {
  59                     // ThreadPoolExecutor will spawn a new thread after core size is reached only if the queue.offer returns false.
  60                     return false;
  61                 }
  62             };
  63
  64             ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("md-sal-binding-notification-%d").build();
  65
  66             ThreadPoolExecutor executor = new ThreadPoolExecutor(CORE_NOTIFICATION_THREADS, MAX_NOTIFICATION_THREADS,
  67                     NOTIFICATION_THREAD_LIFE, TimeUnit.SECONDS, queue , factory,
  68                     new RejectedExecutionHandler() {
  69                         // if the max threads are met, then it will raise a rejectedExecution. We then push to the queue.
  70                         @Override
  71                         public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
  72                             try {
  73                                 executor.getQueue().put(r);
  74                             } catch (InterruptedException e) {
  75                                 Thread.currentThread().interrupt();// set interrupt flag after clearing
  76                                 throw new IllegalStateException(e);
  77                             }
  78                         }
  79                     });
  80
  81             NOTIFICATION_EXECUTOR = MoreExecutors.listeningDecorator(executor);
  82         }
  83
  84         return NOTIFICATION_EXECUTOR;
  85     }
  86
  87     /**
  88      * @deprecated This method is only used from configuration modules and thus callers of it
  89      *             should use service injection to make the executor configurable.
  90      */
  91     @Deprecated
  92     public static synchronized final ListeningExecutorService getDefaultCommitExecutor() {
  93         if (COMMIT_EXECUTOR == null) {
  94             ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("md-sal-binding-commit-%d").build();
  95             /*
  96              * FIXME: this used to be newCacheThreadPool(), but MD-SAL does not have transaction
  97              *        ordering guarantees, which means that using a concurrent threadpool results
  98              *        in application data being committed in random order, potentially resulting
  99              *        in inconsistent data being present. Once proper primitives are introduced,
 100              *        concurrency can be reintroduced.
 101              */
 102             ExecutorService executor = Executors.newSingleThreadExecutor(factory);
 103             COMMIT_EXECUTOR = MoreExecutors.listeningDecorator(executor);
 104         }
 105
 106         return COMMIT_EXECUTOR;
 107     }
 108
 109     public static ExecutorService getDefaultChangeEventExecutor() {
 110         if (CHANGE_EVENT_EXECUTOR == null) {
 111             ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("md-sal-binding-change-%d").build();
 112             /*
 113              * FIXME: this used to be newCacheThreadPool(), but MD-SAL does not have transaction
 114              *        ordering guarantees, which means that using a concurrent threadpool results
 115              *        in application data being committed in random order, potentially resulting
 116              *        in inconsistent data being present. Once proper primitives are introduced,
 117              *        concurrency can be reintroduced.
 118              */
 119             ExecutorService executor = Executors.newSingleThreadExecutor(factory);
 120             CHANGE_EVENT_EXECUTOR  = MoreExecutors.listeningDecorator(executor);
 121         }
 122
 123         return CHANGE_EVENT_EXECUTOR;
 124     }
 125 }