@Override
  protected void finalize() {
    if (cachePersister != null && !cachePersister.isInterrupted()) {
      cachePersister.interrupt();
    }
  }
Needed mostly for UTs that might run in the same VM and create different BucketCache instances
on different UT methods.
hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/bucket/BucketCache.java