@Override
  public long runFrequency(TimeUnit unit) {
    return MetastoreConf.getTimeVar(conf, MetastoreConf.ConfVars.METASTORE_ACIDMETRICS_CHECK_INTERVAL, unit);
  }
Collect and publish ACID and compaction related metrics.
Everything should be behind 2 feature flags: {@link MetastoreConf.ConfVars#METRICS_ENABLED} and
{@link MetastoreConf.ConfVars#METASTORE_ACIDMETRICS_THREAD_ON}.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/metrics/AcidMetricService.java