@Override
  public void endAsyncThread(long start) {
    stats.incLong(asyncThreadInProgressId, -1);
    stats.incLong(asyncThreadCompletedId, 1);
    if (enableClockStats) {
      stats.incLong(asyncThreadTimeId, getTime() - start);
    }
  }
@return the timestamp that marks the start of the operation
geode-core/src/main/java/org/apache/geode/distributed/internal/DistributionStats.java