anchor.diff:  
   %% private 
   
  -set_port_buffers(Port, SendBufSz, RecBufSz) ->
  -    inet:setopts(Port, [{sndbuf, SendBufSz},
  -                        {recbuf, RecBufSz}]).
  +set_port_buffers(Port, SndBuf, RecBuf) ->
  +    inet:setopts(Port, [{sndbuf, SndBuf},
  +                        {recbuf, RecBuf}]).
  
positive.code:     %% register for monitor events so we can adjust buffers on 
      %% new connections when they're started.
      ok = net_kernel:monitor_nodes(true, [{node_type, visible}, nodedown_reason]),
      {SendBufSz, RecBufSz} = get_riak_env_vars(),
      DistCtrl = erlang:system_info(dist_ctrl),
      %% make sure that buffers are correct on existing connections.
      [set_port_buffers(Port, SendBufSz, RecBufSz)
       || {_Node, Port} <- DistCtrl],
      {ok, #state{sndbuf=SendBufSz, recbuf=RecBufSz}}.
  
  get_riak_env_vars() ->
      {ok, SndBufSz} = application:get_env(riak_core, dist_send_buf_size),
      {ok, RecBufSz} = application:get_env(riak_core, dist_recv_buf_size),
      {SndBufSz, RecBufSz}.
  
  handle_call({set_dist_buf_sizes, SendSz, RecvSz}, _From, State) ->
      [set_port_buffers(Port, SendSz, RecvSz)
       || {_Node, Port} <- erlang:system_info(dist_ctrl)],
      {reply, ok, State#state{sndbuf=SendSz, recbuf=RecvSz}};
  handle_call(Msg, _From, State) ->
      lager:warning("unknown call message received: ~p", [Msg]),
      {noreply, State}.
  
negative.code:          }).
  
  %% provided for testing convenience and debugging.
  set_dist_buf_sizes(SndBuf, RecBuf) 
    when (is_integer(SndBuf) andalso SndBuf > 0) andalso
         (is_integer(RecBuf) andalso RecBuf > 0) ->
      gen_server:call(?MODULE, {set_dist_buf_sizes, SndBuf, RecBuf}).
  
  
  start_link() ->
  