YARN任务监控界面Aggregate Resource Allocation指标解析

  // 资源信息更新间隔：3秒
  private static final long MEM_AGGREGATE_ALLOCATION_CACHE_MSECS = 3000;
  // 最后更新时间、最后更新时的每秒的内存和CPU使用量
  protected long lastMemoryAggregateAllocationUpdateTime = 0;
  private long lastMemorySeconds = 0;
  private long lastVcoreSeconds = 0;

 /**
   * 返回任务拥有的所有container每秒所消耗的资源（内存、CPU）总和
   * @return
   */
  synchronized AggregateAppResourceUsage getRunningAggregateAppResourceUsage() {
    long currentTimeMillis = System.currentTimeMillis();
    // Don't walk the whole container list if the resources were computed
    // recently.
    // 判断是否达到更新条件：当前时间 - 最后更新时间 > 最大更新间隔（3秒）
    if ((currentTimeMillis - lastMemoryAggregateAllocationUpdateTime)
        > MEM_AGGREGATE_ALLOCATION_CACHE_MSECS) {
      long memorySeconds = 0;
      long vcoreSeconds = 0;
      // 迭代所有的container，计算每个container每秒所消耗的资源（内存、CPU）
      for (RMContainer rmContainer : this.liveContainers.values()) {
        // 获取container的运行时间
        long usedMillis = currentTimeMillis - rmContainer.getCreationTime(); 
        // 计算container每秒所消耗的资源（内存、CPU）
        Resource resource = rmContainer.getContainer().getResource();
        // 汇总内存和CPU使用量
        memorySeconds += resource.getMemory() * usedMillis /  
            DateUtils.MILLIS_PER_SECOND;
        vcoreSeconds += resource.getVirtualCores() * usedMillis  
            / DateUtils.MILLIS_PER_SECOND;
      }
      
      // 记录最后更新任务资源使用情况的时间、任务最后每秒使用的内存和CPU数量
      lastMemoryAggregateAllocationUpdateTime = currentTimeMillis;
      lastMemorySeconds = memorySeconds;
      lastVcoreSeconds = vcoreSeconds;
    }
    return new AggregateAppResourceUsage(lastMemorySeconds, lastVcoreSeconds);
  }

  /**
   * 返回任务使用的资源情况
   * @return
   */
  public synchronized ApplicationResourceUsageReport getResourceUsageReport() {
    AggregateAppResourceUsage resUsage = getRunningAggregateAppResourceUsage();
    // 返回任务所使用的资源情况：所使用的container数量、预留的container数量、当前消耗的资源、当前预留的资源、所需的总资源（当前消耗的资源+当前预留的资源）、每秒的内存和CPU使用量
    return ApplicationResourceUsageReport.newInstance(liveContainers.size(),
               reservedContainers.size(), Resources.clone(currentConsumption),
               Resources.clone(currentReservation),
               Resources.add(currentConsumption, currentReservation),
               resUsage.getMemorySeconds(), resUsage.getVcoreSeconds());
  }

 @Override
  public ApplicationResourceUsageReport getAppResourceUsageReport(
      ApplicationAttemptId appAttemptId) {
    SchedulerApplicationAttempt attempt = getApplicationAttempt(appAttemptId);
    if (attempt == null) {
      if (LOG.isDebugEnabled()) {
        LOG.debug("Request for appInfo of unknown attempt " + appAttemptId);
      }
      return null;
    }
    return attempt.getResourceUsageReport();
  }