/** Compares our trees, and triggers repairs for any ranges that mismatch. */
      public void run() {
        InetAddress local = FBUtilities.getLocalAddress();

        // restore partitioners (in case we were serialized)
        if (ltree.partitioner() == null) ltree.partitioner(StorageService.getPartitioner());
        if (rtree.partitioner() == null) rtree.partitioner(StorageService.getPartitioner());

        // compare trees, and collect differences
        differences.addAll(MerkleTree.difference(ltree, rtree));

        // choose a repair method based on the significance of the difference
        String format =
            "Endpoints " + local + " and " + remote + " %s for " + cfname + " on " + range;
        if (differences.isEmpty()) {
          logger.info(String.format(format, "are consistent"));
          completed(remote, cfname);
          return;
        }

        // non-0 difference: perform streaming repair
        logger.info(String.format(format, "have " + differences.size() + " range(s) out of sync"));
        try {
          performStreamingRepair();
        } catch (IOException e) {
          throw new RuntimeException(e);
        }
      }