60 lines
1.5 KiB
Erlang
60 lines
1.5 KiB
Erlang
%%%----------------------------------------------------------------------
|
|
%%% File : shaper.erl
|
|
%%% Author : Alexey Shchepin <alexey@sevcom.net>
|
|
%%% Purpose : Functions to control connections traffic
|
|
%%% Created : 9 Feb 2003 by Alexey Shchepin <alexey@sevcom.net>
|
|
%%% Id : $Id$
|
|
%%%----------------------------------------------------------------------
|
|
|
|
-module(shaper).
|
|
-author('alexey@sevcom.net').
|
|
-vsn('$Revision$ ').
|
|
|
|
-export([new/1, new1/1, update/2]).
|
|
|
|
-record(maxrate, {maxrate, lastrate, lasttime}).
|
|
|
|
|
|
new(Name) ->
|
|
Data = case ejabberd_config:get_global_option({shaper, Name, global}) of
|
|
undefined ->
|
|
none;
|
|
D ->
|
|
D
|
|
end,
|
|
new1(Data).
|
|
|
|
|
|
new1(none) ->
|
|
none;
|
|
new1({maxrate, MaxRate}) ->
|
|
#maxrate{maxrate = MaxRate,
|
|
lastrate = 0,
|
|
lasttime = now_to_usec(now())}.
|
|
|
|
|
|
update(none, _Size) ->
|
|
{none, 0};
|
|
update(#maxrate{} = State, Size) ->
|
|
MinInterv = 1000 * Size /
|
|
(2 * State#maxrate.maxrate - State#maxrate.lastrate),
|
|
Interv = (now_to_usec(now()) - State#maxrate.lasttime) / 1000,
|
|
%io:format("State: ~p, Size=~p~nM=~p, I=~p~n",
|
|
% [State, Size, MinInterv, Interv]),
|
|
Pause = if
|
|
MinInterv > Interv ->
|
|
1 + trunc(MinInterv - Interv);
|
|
true ->
|
|
0
|
|
end,
|
|
NextNow = now_to_usec(now()) + Pause * 1000,
|
|
{State#maxrate{
|
|
lastrate = (State#maxrate.lastrate +
|
|
1000000 * Size / (NextNow - State#maxrate.lasttime))/2,
|
|
lasttime = NextNow},
|
|
Pause}.
|
|
|
|
|
|
now_to_usec({MSec, Sec, USec}) ->
|
|
(MSec*1000000 + Sec)*1000000 + USec.
|