hadoop IOStatisticsStoreImpl 源码

  • 2022-10-20
  • 浏览 (292)

haddop IOStatisticsStoreImpl 代码

文件路径:/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/statistics/impl/IOStatisticsStoreImpl.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hadoop.fs.statistics.impl;

import javax.annotation.Nullable;
import java.time.Duration;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.apache.hadoop.fs.statistics.DurationTracker;
import org.apache.hadoop.fs.statistics.IOStatistics;
import org.apache.hadoop.fs.statistics.MeanStatistic;

import static java.util.Objects.requireNonNull;
import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.stubDurationTracker;
import static org.apache.hadoop.fs.statistics.StoreStatisticNames.SUFFIX_MAX;
import static org.apache.hadoop.fs.statistics.StoreStatisticNames.SUFFIX_MEAN;
import static org.apache.hadoop.fs.statistics.StoreStatisticNames.SUFFIX_MIN;
import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.aggregateMaximums;
import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.aggregateMinimums;
import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.dynamicIOStatistics;
import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.maybeUpdateMaximum;
import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.maybeUpdateMinimum;

/**
 * Implementation of {@link IOStatisticsStore}.
 * <p>
 *   A ConcurrentHashMap of each set of statistics is created;
 *   the AtomicLong/MeanStatistic entries are fetched as required.
 *   When the statistics are updated, the referenced objects
 *   are updated rather than new values set in the map.
 * </p>
 */
final class IOStatisticsStoreImpl extends WrappedIOStatistics
    implements IOStatisticsStore {

  /**
   * Log changes at debug.
   * Noisy, but occasionally useful.
   */
  private static final Logger LOG =
      LoggerFactory.getLogger(IOStatisticsStoreImpl.class);

  /** All the counters are atomic longs. */
  private final Map<String, AtomicLong> counterMap = new ConcurrentHashMap<>();

  /** All the gauges are atomic longs. */
  private final Map<String, AtomicLong> gaugeMap = new ConcurrentHashMap<>();

  /** All the minimum values are atomic longs. */
  private final Map<String, AtomicLong> minimumMap = new ConcurrentHashMap<>();

  /** All the maximum values are atomic longs. */
  private final Map<String, AtomicLong> maximumMap = new ConcurrentHashMap<>();

  /**
   * The mean statistics.
   * Relies on the MeanStatistic operations being synchronized.
   */
  private final Map<String, MeanStatistic> meanStatisticMap
      = new ConcurrentHashMap<>();

  /**
   * Constructor invoked via the builder.
   * @param counters keys to use for the counter statistics.
   * @param gauges names of gauges
   * @param minimums names of minimums
   * @param maximums names of maximums
   * @param meanStatistics names of mean statistics.
   */
  IOStatisticsStoreImpl(
      final List<String> counters,
      final List<String> gauges,
      final List<String> minimums,
      final List<String> maximums,
      final List<String> meanStatistics) {
    // initially create the superclass with no wrapped mapping;
    super(null);

    // now construct a dynamic statistics source mapping to
    // the various counters, gauges etc dynamically created
    // into maps
    DynamicIOStatisticsBuilder builder = dynamicIOStatistics();
    if (counters != null) {
      for (String key : counters) {
        AtomicLong counter = new AtomicLong();
        counterMap.put(key, counter);
        builder.withAtomicLongCounter(key, counter);
      }
    }
    if (gauges != null) {
      for (String key : gauges) {
        AtomicLong gauge = new AtomicLong();
        gaugeMap.put(key, gauge);
        builder.withAtomicLongGauge(key, gauge);
      }
    }
    if (maximums != null) {
      for (String key : maximums) {
        AtomicLong maximum = new AtomicLong(MAX_UNSET_VALUE);
        maximumMap.put(key, maximum);
        builder.withAtomicLongMaximum(key, maximum);
      }
    }
    if (minimums != null) {
      for (String key : minimums) {
        AtomicLong minimum = new AtomicLong(MIN_UNSET_VALUE);
        minimumMap.put(key, minimum);
        builder.withAtomicLongMinimum(key, minimum);
      }
    }
    if (meanStatistics != null) {
      for (String key : meanStatistics) {
        meanStatisticMap.put(key, new MeanStatistic());
        builder.withMeanStatisticFunction(key, k -> meanStatisticMap.get(k));
      }
    }
    setWrapped(builder.build());
  }

  /**
   * Set an atomic long to a value.
   * @param aLong atomic long; may be null
   * @param value value to set to
   */
  private void setAtomicLong(final AtomicLong aLong, final long value) {
    if (aLong != null) {
      aLong.set(value);
    }
  }

  /**
   * increment an atomic long and return its value;
   * null long is no-op returning 0.
   * @param aLong atomic long; may be null
   * param increment amount to increment; negative for a decrement
   * @return final value or 0 if the long is null
   */
  private long incAtomicLong(final AtomicLong aLong,
      final long increment) {
    if (aLong != null) {
      // optimization: zero is a get rather than addAndGet()
      return increment != 0
          ? aLong.addAndGet(increment)
          : aLong.get();
    } else {
      return 0;
    }
  }

  @Override
  public void setCounter(final String key, final long value) {
    setAtomicLong(counterMap.get(key), value);
    LOG.debug("Setting counter {} to {}", key, value);
  }

  @Override
  public long incrementCounter(final String key, final long value) {
    AtomicLong counter = counterMap.get(key);
    if (counter == null) {
      LOG.debug("Ignoring counter increment for unknown counter {}",
          key);
      return 0;
    }
    if (value < 0) {
      LOG.debug("Ignoring negative increment value {} for counter {}",
          value, key);
      // returns old value
      return counter.get();
    } else {
      long l = incAtomicLong(counter, value);
      LOG.debug("Incrementing counter {} by {} with final value {}",
          key, value, l);
      return l;
    }
  }

  @Override
  public void setMaximum(final String key, final long value) {
    setAtomicLong(maximumMap.get(key), value);
  }

  @Override
  public long incrementMaximum(final String key, final long value) {
    return incAtomicLong(maximumMap.get(key), value);
  }

  @Override
  public void setMinimum(final String key, final long value) {
    setAtomicLong(minimumMap.get(key), value);
  }

  @Override
  public long incrementMinimum(final String key, final long value) {
    return incAtomicLong(minimumMap.get(key), value);
  }

  @Override
  public void addMinimumSample(final String key, final long value) {
    AtomicLong min = minimumMap.get(key);
    if (min != null) {
      maybeUpdateMinimum(min, value);
    }
  }

  @Override
  public void addMaximumSample(final String key, final long value) {
    AtomicLong max = maximumMap.get(key);
    if (max != null) {
      maybeUpdateMaximum(max, value);
    }
  }

  @Override
  public void setGauge(final String key, final long value) {
    setAtomicLong(gaugeMap.get(key), value);
  }

  @Override
  public long incrementGauge(final String key, final long value) {
    return incAtomicLong(gaugeMap.get(key), value);
  }

  @Override
  public void setMeanStatistic(final String key, final MeanStatistic value) {
    final MeanStatistic ref = meanStatisticMap.get(key);
    if (ref != null) {
      ref.set(value);
    }
  }

  @Override
  public void addMeanStatisticSample(final String key, final long value) {
    final MeanStatistic ref = meanStatisticMap.get(key);
    if (ref != null) {
      ref.addSample(value);
    }
  }

  /**
   * Reset all statistics.
   */
  @Override
  public synchronized void reset() {
    counterMap.values().forEach(a -> a.set(0));
    gaugeMap.values().forEach(a -> a.set(0));
    minimumMap.values().forEach(a -> a.set(0));
    maximumMap.values().forEach(a -> a.set(0));
    meanStatisticMap.values().forEach(a -> a.clear());
  }

  /**
   * Aggregate those statistics which the store is tracking;
   * ignore the rest.
   *
   * @param source statistics; may be null
   * @return true if a statistics reference was supplied/aggregated.
   */
  @Override
  public synchronized boolean aggregate(
      @Nullable final IOStatistics source) {

    if (source == null) {
      return false;
    }
    // counters: addition
    Map<String, Long> sourceCounters = source.counters();
    counterMap.entrySet().
        forEach(e -> {
          Long sourceValue = lookupQuietly(sourceCounters, e.getKey());
          if (sourceValue != null) {
            e.getValue().addAndGet(sourceValue);
          }
        });
    // gauge: add positive values only
    Map<String, Long> sourceGauges = source.gauges();
    gaugeMap.entrySet().forEach(e -> {
      Long sourceGauge = lookupQuietly(sourceGauges, e.getKey());
      if (sourceGauge != null && sourceGauge > 0) {
        e.getValue().addAndGet(sourceGauge);
      }
    });
    // min: min of current and source
    Map<String, Long> sourceMinimums = source.minimums();
    minimumMap.entrySet().forEach(e -> {
      Long sourceValue = lookupQuietly(sourceMinimums, e.getKey());
      if (sourceValue != null) {
        AtomicLong dest = e.getValue();
        dest.set(aggregateMaximums(dest.get(), sourceValue));
        dest.set(aggregateMinimums(dest.get(), sourceValue));
      }
    });
    // max: max of current and source
    Map<String, Long> sourceMaximums = source.maximums();
    maximumMap.entrySet().forEach(e -> {
      Long sourceValue = lookupQuietly(sourceMaximums, e.getKey());
      if (sourceValue != null) {
        AtomicLong dest = e.getValue();
        dest.set(aggregateMaximums(dest.get(), sourceValue));
      }
    });
    // the most complex
    Map<String, MeanStatistic> sourceMeans = source.meanStatistics();
    meanStatisticMap.entrySet().forEach(e -> {
      MeanStatistic current = e.getValue();
      MeanStatistic sourceValue = lookupQuietly(
          sourceMeans, e.getKey());
      if (sourceValue != null) {
        current.add(sourceValue);
      }
    });
    return true;
  }

  /**
   * Get a reference to the map type providing the
   * value for a specific key, raising an exception if
   * there is no entry for that key.
   * @param <T> type of map/return type.
   * @param map map to look up
   * @param key statistic name
   * @return the value
   * @throws NullPointerException if there is no entry of that name
   */
  private static <T> T lookup(final Map<String, T> map, String key) {
    T val = map.get(key);
    requireNonNull(val, () -> ("unknown statistic " + key));
    return val;
  }

  /**
   * Get a reference to the map type providing the
   * value for a specific key, returning null if it not found.
   * @param <T> type of map/return type.
   * @param map map to look up
   * @param key statistic name
   * @return the value
   */
  private static <T> T lookupQuietly(final Map<String, T> map, String key) {
    return map.get(key);
  }

  /**
   * Get a reference to the atomic instance providing the
   * value for a specific counter. This is useful if
   * the value is passed around.
   * @param key statistic name
   * @return the reference
   * @throws NullPointerException if there is no entry of that name
   */
  @Override
  public AtomicLong getCounterReference(String key) {
    return lookup(counterMap, key);
  }

  /**
   * Get a reference to the atomic instance providing the
   * value for a specific maximum. This is useful if
   * the value is passed around.
   * @param key statistic name
   * @return the reference
   * @throws NullPointerException if there is no entry of that name
   */
  @Override
  public AtomicLong getMaximumReference(String key) {
    return lookup(maximumMap, key);
  }

  /**
   * Get a reference to the atomic instance providing the
   * value for a specific minimum. This is useful if
   * the value is passed around.
   * @param key statistic name
   * @return the reference
   * @throws NullPointerException if there is no entry of that name
   */
  @Override
  public AtomicLong getMinimumReference(String key) {
    return lookup(minimumMap, key);
  }

  /**
   * Get a reference to the atomic instance providing the
   * value for a specific gauge. This is useful if
   * the value is passed around.
   * @param key statistic name
   * @return the reference
   * @throws NullPointerException if there is no entry of that name
   */
  @Override
  public AtomicLong getGaugeReference(String key) {
    return lookup(gaugeMap, key);
  }

  /**
   * Get a mean statistic.
   * @param key statistic name
   * @return the reference
   * @throws NullPointerException if there is no entry of that name
   */
  @Override
  public MeanStatistic getMeanStatistic(String key) {
    return lookup(meanStatisticMap, key);
  }

  /**
   * Add a duration to the min/mean/max statistics, using the
   * given prefix and adding a suffix for each specific value.
   * <p>
   * The update is non -atomic, even though each individual statistic
   * is updated thread-safely. If two threads update the values
   * simultaneously, at the end of each operation the state will
   * be correct. It is only during the sequence that the statistics
   * may be observably inconsistent.
   * </p>
   * @param prefix statistic prefix
   * @param durationMillis duration in milliseconds.
   */
  @Override
  public void addTimedOperation(String prefix, long durationMillis) {
    addMeanStatisticSample(prefix + SUFFIX_MEAN, durationMillis);
    addMinimumSample(prefix + SUFFIX_MIN, durationMillis);
    addMaximumSample(prefix + SUFFIX_MAX, durationMillis);
  }

  @Override
  public void addTimedOperation(String prefix, Duration duration) {
    addTimedOperation(prefix, duration.toMillis());
  }

  /**
   * If the store is tracking the given key, return the
   * duration tracker for it. If not tracked, return the
   * stub tracker.
   * @param key statistic key prefix
   * @param count  #of times to increment the matching counter in this
   * operation.
   * @return a tracker.
   */
  @Override
  public DurationTracker trackDuration(final String key, final long count) {
    if (counterMap.containsKey(key)) {
      return new StatisticDurationTracker(this, key, count);
    } else {
      return stubDurationTracker();
    }
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop AbstractIOStatisticsImpl 源码

hadoop DynamicIOStatistics 源码

hadoop DynamicIOStatisticsBuilder 源码

hadoop EmptyIOStatistics 源码

hadoop EmptyIOStatisticsContextImpl 源码

hadoop EmptyIOStatisticsStore 源码

hadoop EvaluatingStatisticsMap 源码

hadoop IOStatisticsBinding 源码

hadoop IOStatisticsContextImpl 源码

hadoop IOStatisticsContextIntegration 源码

0  赞