/**
     * @param newEntries Infos.
     * @param lsnr Listener for the operation future.
     * @throws GridInterruptedException If failed.
     * @return Future for operation.
     */
    @Nullable
    GridFutureAdapter<?> update(
        Iterable<Map.Entry<K, V>> newEntries, GridInClosure<GridFuture<?>> lsnr)
        throws GridInterruptedException {
      List<Map.Entry<K, V>> entries0 = null;
      GridFutureAdapter<Object> curFut0;

      synchronized (this) {
        curFut0 = curFut;

        curFut0.listenAsync(lsnr);

        for (Map.Entry<K, V> entry : newEntries) entries.add(entry);

        if (entries.size() >= bufSize) {
          entries0 = entries;

          entries = newEntries();
          curFut = new GridFutureAdapter<>(ctx);
          curFut.listenAsync(signalC);
        }
      }

      if (entries0 != null) {
        submit(entries0, curFut0);

        if (cancelled)
          curFut0.onDone(
              new GridException("Data loader has been cancelled: " + GridDataLoaderImpl.this));
      }

      return curFut0;
    }
    /** @param node Node. */
    Buffer(GridNode node) {
      assert node != null;

      this.node = node;

      locFuts = new GridConcurrentHashSet<>();
      reqs = new ConcurrentHashMap8<>();

      // Cache local node flag.
      isLocNode = node.equals(ctx.discovery().localNode());

      entries = newEntries();
      curFut = new GridFutureAdapter<>(ctx);
      curFut.listenAsync(signalC);

      sem = new Semaphore(parallelOps);
    }
    /**
     * @return Future if any submitted.
     * @throws GridInterruptedException If thread has been interrupted.
     */
    @Nullable
    GridFuture<?> flush() throws GridInterruptedException {
      List<Map.Entry<K, V>> entries0 = null;
      GridFutureAdapter<Object> curFut0 = null;

      synchronized (this) {
        if (!entries.isEmpty()) {
          entries0 = entries;
          curFut0 = curFut;

          entries = newEntries();
          curFut = new GridFutureAdapter<>(ctx);
          curFut.listenAsync(signalC);
        }
      }

      if (entries0 != null) submit(entries0, curFut0);

      // Create compound future for this flush.
      GridCompoundFuture<Object, Object> res = null;

      for (GridFuture<Object> f : locFuts) {
        if (res == null) res = new GridCompoundFuture<>(ctx);

        res.add(f);
      }

      for (GridFuture<Object> f : reqs.values()) {
        if (res == null) res = new GridCompoundFuture<>(ctx);

        res.add(f);
      }

      if (res != null) res.markInitialized();

      return res;
    }
  /** {@inheritDoc} */
  @Override
  public GridFuture<?> addData(Collection<? extends Map.Entry<K, V>> entries) {
    A.notEmpty(entries, "entries");

    enterBusy();

    try {
      GridFutureAdapter<Object> resFut = new GridFutureAdapter<>(ctx);

      activeFuts.add(resFut);

      resFut.listenAsync(rmvActiveFut);

      Collection<K> keys = new GridConcurrentHashSet<>(entries.size(), 1.0f, 16);

      for (Map.Entry<K, V> entry : entries) keys.add(entry.getKey());

      load0(entries, resFut, keys, 0);

      return resFut;
    } finally {
      leaveBusy();
    }
  }