From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [patch net-next v2 06/11] tbf: improved accuracy at high rates Date: Fri, 08 Feb 2013 11:09:48 -0800 Message-ID: <1360350588.28557.107.camel@edumazet-glaptop> References: <1360349981-27801-1-git-send-email-jiri@resnulli.us> <1360349981-27801-7-git-send-email-jiri@resnulli.us> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com, jhs@mojatatu.com, kuznet@ms2.inr.ac.ru, j.vimal@gmail.com To: Jiri Pirko Return-path: Received: from mail-ia0-f171.google.com ([209.85.210.171]:61940 "EHLO mail-ia0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760295Ab3BHTJv (ORCPT ); Fri, 8 Feb 2013 14:09:51 -0500 Received: by mail-ia0-f171.google.com with SMTP id z13so4601156iaz.2 for ; Fri, 08 Feb 2013 11:09:50 -0800 (PST) In-Reply-To: <1360349981-27801-7-git-send-email-jiri@resnulli.us> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 2013-02-08 at 19:59 +0100, Jiri Pirko wrote: > Current TBF uses rate table computed by the "tc" userspace program, > which has the following issue: > > The rate table has 256 entries to map packet lengths to > token (time units). With TSO sized packets, the 256 entry granularity > leads to loss/gain of rate, making the token bucket inaccurate. > > Thus, instead of relying on rate table, this patch explicitly computes > the time and accounts for packet transmission times with nanosecond > granularity. > > This is a followup to 56b765b79e9a78dc7d3f8850ba5e5567205a3ecd > > Signed-off-by: Jiri Pirko > --- Acked-by: Eric Dumazet