@Override
  public EvictionController getExistingController(InternalRegionArguments internalArgs) {
    if (isBucket()) {
      return getDiskStore().getOrCreatePRLRUStats(this);
    }
    return null;
  }
This constructor is used when we are closing an existing region. We want to remember that it is
still present in the disk store.
geode-core/src/main/java/org/apache/geode/internal/cache/PlaceHolderDiskRegion.java