public boolean isIndexSane() {
      return throwable == null && duplicatePuts.size() == 0 && putAfterUpdates.size() == 0
          && duplicateDeletes.size() == 0 && duplicateUpdates.size() == 0 && updateAfterDeletes.size() == 0
          && duplicateKeys.size() == 0;
    }
@return {@code true} if there are no duplicate puts or deletes or updates and no puts after updates or updates
after deletes. {@code false} otherwise
ambry-tools/src/main/java/com/github/ambry/store/DumpIndexTool.java