public long startPrimaryTransfer(boolean isRebalance) {
    stats.incLong(primaryTransfersInProgressId, 1);
    if (isRebalance) {
      startRebalancePrimaryTransfer();
    }
    return clock.getTime();
  }
This method sets the end time for update and updates the counters
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionedRegionStats.java