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 javax.annotation.Nullable;
  23 import org.opendaylight.openflowplugin.api.ConnectionException;
  24
  25 public class StatisticsPollingService extends AbstractScheduledService {
  26     private static final long DEFAULT_STATS_TIMEOUT = 50000;
  27
  28     private final TimeCounter counter;
  29     private final long pollingInterval;
  30     private final long maximumTimerDelay;
  31     private final Supplier<ListenableFuture<Boolean>> gatheringSupplier;
  32     private final SettableFuture<Void> future = SettableFuture.create();
  33
  34     StatisticsPollingService(@Nonnull final TimeCounter counter,
  35                              final long pollingInterval,
  36                              final long maximumTimerDelay,
  37                              @Nonnull final Supplier<ListenableFuture<Boolean>> gatheringSupplier) {
  38         this.counter = counter;
  39         this.pollingInterval = pollingInterval;
  40         this.maximumTimerDelay = maximumTimerDelay;
  41         this.gatheringSupplier = gatheringSupplier;
  42         this.addListener(new StatisticsPollingServiceListener(), MoreExecutors.directExecutor());
  43     }
  44
  45     ListenableFuture<Void> stop() {
  46         stopAsync();
  47         return future;
  48     }
  49
  50     @Override
  51     protected void startUp() throws Exception {
  52         counter.markStart();
  53     }
  54
  55     @Override
  56     protected void runOneIteration() throws Exception {
  57         final long averageTime = counter.getAverageTimeBetweenMarks();
  58         final long statsTimeout = averageTime > 0 ? 3 * averageTime : DEFAULT_STATS_TIMEOUT;
  59         final CompletableFuture<Boolean> waitFuture = new CompletableFuture<>();
  60
  61         Futures.addCallback(gatheringSupplier.get(), new FutureCallback<Boolean>() {
  62             @Override
  63             public void onSuccess(@Nullable final Boolean result) {
  64                 waitFuture.complete(result);
  65             }
  66
  67             @Override
  68             public void onFailure(@Nonnull final Throwable throwable) {
  69                 waitFuture.completeExceptionally(throwable);
  70             }
  71         }, MoreExecutors.directExecutor());
  72
  73         try {
  74             waitFuture.get(statsTimeout, TimeUnit.MILLISECONDS);
  75         } finally {
  76             counter.addTimeMark();
  77         }
  78     }
  79
  80     @Override
  81     protected Scheduler scheduler() {
  82         final long averageStatisticsGatheringTime = counter.getAverageTimeBetweenMarks();
  83         long currentTimerDelay = pollingInterval;
  84
  85         if (averageStatisticsGatheringTime > currentTimerDelay) {
  86             currentTimerDelay = averageStatisticsGatheringTime;
  87
  88             if (currentTimerDelay > maximumTimerDelay) {
  89                 currentTimerDelay = maximumTimerDelay;
  90             }
  91         }
  92
  93         return Scheduler.newFixedDelaySchedule(currentTimerDelay, currentTimerDelay, TimeUnit.MILLISECONDS);
  94     }
  95
  96     private final class StatisticsPollingServiceListener extends Service.Listener {
  97         @Override
  98         public void terminated(final Service.State from) {
  99             super.terminated(from);
 100             future.set(null);
 101         }
 102
 103         @Override
 104         public void failed(final Service.State from, final Throwable failure) {
 105             super.failed(from, failure);
 106             if (!(failure instanceof CancellationException) && !(failure instanceof ConnectionException)) {
 107                 future.setException(failure);
 108             } else {
 109                 future.set(null);
 110             }
 111         }
 112     }
 113 }