@Override
  public void onDropPartition(DropPartitionEvent partitionEvent) throws MetaException {
    Metrics.getOrCreateGauge(MetricsConstants.TOTAL_PARTITIONS).decrementAndGet();
    deletedParts.inc();
  }
Report metrics of metadata added, deleted by this Hive Metastore.
The listener is only attached when the metrics are enabled.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/HMSMetricsListener.java