From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750994AbVHWRV2 (ORCPT ); Tue, 23 Aug 2005 13:21:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932234AbVHWRV2 (ORCPT ); Tue, 23 Aug 2005 13:21:28 -0400 Received: from [62.206.217.67] ([62.206.217.67]:53683 "EHLO kaber.coreworks.de") by vger.kernel.org with ESMTP id S1750905AbVHWRV1 (ORCPT ); Tue, 23 Aug 2005 13:21:27 -0400 Message-ID: <430B5B14.5070105@trash.net> Date: Tue, 23 Aug 2005 19:21:24 +0200 From: Patrick McHardy User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.10) Gecko/20050803 Debian/1.7.10-1 X-Accept-Language: en MIME-Version: 1.0 To: danial_thom@yahoo.com CC: Helge Hafting , linux-kernel@vger.kernel.org Subject: Re: 2.6.12 Performance problems References: <20050823171028.47315.qmail@web33309.mail.mud.yahoo.com> In-Reply-To: <20050823171028.47315.qmail@web33309.mail.mud.yahoo.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Danial Thom wrote: > I think part of the problem is the continued > misuse of the word "latency". Latency, in > language terms, means "unexplained delay". Its > wrong here because for one, its explainable. But > it also depends on your perspective. The > "latency" is increased for kernel tasks, while it > may be reduced for something that is getting the > benefit of preempting the kernel. So you really > can't say "the price of reduced latency is lower > throughput", because thats simply backwards. > You've increased the kernel tasks latency by > allowing it to be pre-empted. Reduced latency > implies higher efficiency. All you've done here > is shift the latency from one task to another, so > there is no reduction overall, in fact there is > probably a marginal increase due to the overhead > of pre-emption vs doing nothing. If instead of complaining you would provide the information I've asked for two days ago someone might actually be able to help you.