/** {@inheritDoc} */
  @Override
  public GridDhtPartitionFullMap partitionMap(boolean onlyActive) {
    lock.readLock().lock();

    try {
      assert node2part != null && node2part.valid()
          : "Invalid node2part [node2part: "
              + node2part
              + ", cache="
              + cctx.name()
              + ", started="
              + cctx.started()
              + ", stopping="
              + stopping
              + ", locNodeId="
              + cctx.localNode().id()
              + ", locName="
              + cctx.gridName()
              + ']';

      GridDhtPartitionFullMap m = node2part;

      return new GridDhtPartitionFullMap(
          m.nodeId(), m.nodeOrder(), m.updateSequence(), m, onlyActive);
    } finally {
      lock.readLock().unlock();
    }
  }
  /** @param nodeId Node to remove. */
  private void removeNode(UUID nodeId) {
    assert nodeId != null;
    assert lock.writeLock().isHeldByCurrentThread();

    ClusterNode oldest = CU.oldestAliveCacheServerNode(cctx.shared(), topVer);

    assert oldest != null;

    ClusterNode loc = cctx.localNode();

    if (node2part != null) {
      if (oldest.equals(loc) && !node2part.nodeId().equals(loc.id())) {
        updateSeq.setIfGreater(node2part.updateSequence());

        node2part =
            new GridDhtPartitionFullMap(
                loc.id(), loc.order(), updateSeq.incrementAndGet(), node2part, false);
      } else node2part = new GridDhtPartitionFullMap(node2part, node2part.updateSequence());

      part2node = new HashMap<>(part2node);

      GridDhtPartitionMap parts = node2part.remove(nodeId);

      if (parts != null) {
        for (Integer p : parts.keySet()) {
          Set<UUID> nodeIds = part2node.get(p);

          if (nodeIds != null) {
            nodeIds.remove(nodeId);

            if (nodeIds.isEmpty()) part2node.remove(p);
          }
        }
      }

      consistencyCheck();
    }
  }
  /**
   * Updates value for single partition.
   *
   * @param p Partition.
   * @param nodeId Node ID.
   * @param state State.
   * @param updateSeq Update sequence.
   */
  @SuppressWarnings({"MismatchedQueryAndUpdateOfCollection"})
  private void updateLocal(int p, UUID nodeId, GridDhtPartitionState state, long updateSeq) {
    assert lock.isWriteLockedByCurrentThread();
    assert nodeId.equals(cctx.nodeId());

    // In case if node joins, get topology at the time of joining node.
    ClusterNode oldest = CU.oldestAliveCacheServerNode(cctx.shared(), topVer);

    assert oldest != null;

    // If this node became the oldest node.
    if (oldest.id().equals(cctx.nodeId())) {
      long seq = node2part.updateSequence();

      if (seq != updateSeq) {
        if (seq > updateSeq) {
          if (this.updateSeq.get() < seq) {
            // Update global counter if necessary.
            boolean b = this.updateSeq.compareAndSet(this.updateSeq.get(), seq + 1);

            assert b
                : "Invalid update sequence [updateSeq="
                    + updateSeq
                    + ", seq="
                    + seq
                    + ", curUpdateSeq="
                    + this.updateSeq.get()
                    + ", node2part="
                    + node2part.toFullString()
                    + ']';

            updateSeq = seq + 1;
          } else updateSeq = seq;
        }

        node2part.updateSequence(updateSeq);
      }
    }

    GridDhtPartitionMap map = node2part.get(nodeId);

    if (map == null)
      node2part.put(
          nodeId,
          map =
              new GridDhtPartitionMap(
                  nodeId,
                  updateSeq,
                  Collections.<Integer, GridDhtPartitionState>emptyMap(),
                  false));

    map.updateSequence(updateSeq);

    map.put(p, state);

    Set<UUID> ids = part2node.get(p);

    if (ids == null) part2node.put(p, ids = U.newHashSet(3));

    ids.add(nodeId);
  }