@Override
  public void purge(List<MessageInfo> infosToPurge) throws StoreException {
    // TODO Efficient_Metadata_Operations_TODO : implement purge.
  }
Checks the used capacity of the store against the configured percentage thresholds to see if the store
should be read-only or read-write
ambry-store/src/main/java/com/github/ambry/store/BlobStore.java