}

    /**
     * Get a send region from the pool or allocate a new one
     *
     * @param minSize minimum required size
     * @return memory region for sending
     * @throws IOException if allocation fails
     */
    public RdmaMemoryRegion getSendRegion(int minSize) throws IOException {
        if (minSize <= sendBufferSize) {
            RdmaMemoryRegion region = availableSendRegions.poll();

     * SetView}.
     */
    abstract int minSize();

    /**
     * Returns the {@link #minSize()} of {@code set} if it is a {@link SetView}, or the exact {@link
     * #size()} of {@code set} otherwise.
     */
    static int minSize(Set<?> set) {
      return set instanceof SetView ? ((SetView<?>) set).minSize() : set.size();
    }

    /**

  }

  /**
   * Returns a {@link SetView} with a {@link SetView#minSize()} of {@code min} and a {@link
   * SetView#maxSize()} of {@code max}.
   */
  private static SetView<Integer> setSizeRange(int min, int max) {
    checkArgument(min >= 0 && max >= min);
    SetView<Integer> set = difference(setSize(max), setSize(max - min));
    checkState(set.minSize() == min && set.maxSize() == max);
    return set;
  }

  /**

            } catch (IOException e) {
                log.warn("Failed to pre-allocate receive buffer", e);
            }
        }
    }
    
    public RdmaMemoryRegion getSendRegion(int minSize) throws IOException {
        if (minSize <= sendBufferSize) {
            RdmaMemoryRegion region = availableSendRegions.poll();
            if (region != null) {
                region.getBuffer().clear();
                return region;