openflowplugin-impl/src/main/java/org/opendaylight/openflowplugin/impl/statistics/StatisticsPollingService.java

   1 /*
   2  * Copyright (c) 2017 Pantheon Technologies s.r.o. 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.openflowplugin.impl.statistics;
   9
  10 import com.google.common.util.concurrent.AbstractScheduledService;
  11 import com.google.common.util.concurrent.FutureCallback;
  12 import com.google.common.util.concurrent.Futures;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import com.google.common.util.concurrent.MoreExecutors;
  15 import com.google.common.util.concurrent.Service;
  16 import com.google.common.util.concurrent.SettableFuture;
  17 import java.util.concurrent.CancellationException;
  18 import java.util.concurrent.CompletableFuture;
  19 import java.util.concurrent.TimeUnit;
  20 import java.util.function.Supplier;
  21 import javax.annotation.Nonnull;
  22 import org.opendaylight.openflowplugin.api.ConnectionException;
  23
  24 public class StatisticsPollingService extends AbstractScheduledService {
  25     private static final long DEFAULT_STATS_TIMEOUT = 50000;
  26
  27     private final TimeCounter counter;
  28     private final long pollingInterval;
  29     private final long maximumTimerDelay;
  30     private final Supplier<ListenableFuture<Boolean>> gatheringSupplier;
  31     private final SettableFuture<Void> future = SettableFuture.create();
  32
  33     StatisticsPollingService(@Nonnull final TimeCounter counter,
  34                              final long pollingInterval,
  35                              final long maximumTimerDelay,
  36                              @Nonnull final Supplier<ListenableFuture<Boolean>> gatheringSupplier) {
  37         this.counter = counter;
  38         this.pollingInterval = pollingInterval;
  39         this.maximumTimerDelay = maximumTimerDelay;
  40         this.gatheringSupplier = gatheringSupplier;
  41         this.addListener(new StatisticsPollingServiceListener(), MoreExecutors.directExecutor());
  42     }
  43
  44     ListenableFuture<Void> stop() {
  45         stopAsync();
  46         return future;
  47     }
  48
  49     @Override
  50     protected void startUp() {
  51         counter.markStart();
  52     }
  53
  54     @Override
  55     protected void runOneIteration() throws Exception {
  56         final long averageTime = counter.getAverageTimeBetweenMarks();
  57         final long statsTimeout = averageTime > 0 ? 3 * averageTime : DEFAULT_STATS_TIMEOUT;
  58         final CompletableFuture<Boolean> waitFuture = new CompletableFuture<>();
  59
  60         Futures.addCallback(gatheringSupplier.get(), new FutureCallback<Boolean>() {
  61             @Override
  62             public void onSuccess(final Boolean result) {
  63                 waitFuture.complete(result);
  64             }
  65
  66             @Override
  67             public void onFailure(final Throwable throwable) {
  68                 waitFuture.completeExceptionally(throwable);
  69             }
  70         }, MoreExecutors.directExecutor());
  71
  72         try {
  73             waitFuture.get(statsTimeout, TimeUnit.MILLISECONDS);
  74         } finally {
  75             counter.addTimeMark();
  76         }
  77     }
  78
  79     @Override
  80     protected Scheduler scheduler() {
  81         final long averageStatisticsGatheringTime = counter.getAverageTimeBetweenMarks();
  82         long currentTimerDelay = pollingInterval;
  83
  84         if (averageStatisticsGatheringTime > currentTimerDelay) {
  85             currentTimerDelay = averageStatisticsGatheringTime;
  86
  87             if (currentTimerDelay > maximumTimerDelay) {
  88                 currentTimerDelay = maximumTimerDelay;
  89             }
  90         }
  91
  92         return Scheduler.newFixedDelaySchedule(currentTimerDelay, currentTimerDelay, TimeUnit.MILLISECONDS);
  93     }
  94
  95     private final class StatisticsPollingServiceListener extends Service.Listener {
  96         @Override
  97         public void terminated(final Service.State from) {
  98             super.terminated(from);
  99             future.set(null);
 100         }
 101
 102         @Override
 103         public void failed(final Service.State from, final Throwable failure) {
 104             super.failed(from, failure);
 105             if (!(failure instanceof CancellationException) && !(failure instanceof ConnectionException)) {
 106                 future.setException(failure);
 107             } else {
 108                 future.set(null);
 109             }
 110         }
 111     }
 112 }