public void addGauge(String metricName, Gauge<Object> gauge) {
    metricGroup.gauge(metricName, gauge);
  }
Closes the RocksDB instance and cleans up the Guava cache.

<p>Additionally, it shuts down the write-service and clears the RocksDB record queue if they
exist.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/lookup/RocksDBCacheState.java