long getProgress() {
    StoreFindToken token = (StoreFindToken) startToken;
    return token.getType().equals(FindTokenType.Uninitialized) ? 0
        : index.getAbsolutePositionInLogForOffset(token.getOffset());
  }
Gets the number of bytes processed so far
@return the number of bytes processed so far as represented by the start token. Note that if the token is
index based, this is at segment granularity.
ambry-store/src/main/java/com/github/ambry/store/HardDeleter.java