From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751922AbXCTX4L (ORCPT ); Tue, 20 Mar 2007 19:56:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751624AbXCTX4K (ORCPT ); Tue, 20 Mar 2007 19:56:10 -0400 Received: from shawidc-mo1.cg.shawcable.net ([24.71.223.10]:52048 "EHLO pd3mo1so.prod.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbXCTX4I (ORCPT ); Tue, 20 Mar 2007 19:56:08 -0400 Date: Tue, 20 Mar 2007 17:55:31 -0600 From: Robert Hancock Subject: Re: UDP packets scheduling In-reply-to: To: Lukas Hejtmanek , linux-kernel Cc: Andi Kleen Message-id: <46007473.7070001@shaw.ca> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-2; format=flowed Content-transfer-encoding: 7bit References: User-Agent: Thunderbird 1.5.0.10 (Windows/20070221) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Lukas Hejtmanek wrote: > On Tue, Mar 20, 2007 at 06:52:51PM +0100, Andi Kleen wrote: >>> Flow control must be turned off for some other reason. >> That's your fundamental problem. Fix that. >> >> Even if you get the rate right there can be many reasons why timing >> gets disrupted temporarily and to recover from any of this you need >> working flow control. > > How do you want to enable wire/fibre flow control, e.g., from Europe to USA? > You are not guaranteed any hardware based flow control. > > And as of software flow control, you need precise timing of UDP packets to > keep desired packet rate. How to do it at speeds about 5.5Gbps, that is my > question. Why is it necessary to avoid bursting? There should be enough buffering along the chain to avoid packet loss with reasonable burst sizes. -- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@nospamshaw.ca Home Page: http://www.roberthancock.com/