From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265333AbUBBKak (ORCPT ); Mon, 2 Feb 2004 05:30:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265336AbUBBKak (ORCPT ); Mon, 2 Feb 2004 05:30:40 -0500 Received: from mx1.elte.hu ([157.181.1.137]:6333 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S265333AbUBBKaj (ORCPT ); Mon, 2 Feb 2004 05:30:39 -0500 Date: Mon, 2 Feb 2004 11:31:22 +0100 From: Ingo Molnar To: Con Kolivas Cc: linux kernel mailing list , Jos Hulzink Subject: Re: [PATCH] 2.6.1 Hyperthread smart "nice" 2 Message-ID: <20040202103122.GA29402@elte.hu> References: <200401291917.42087.kernel@kolivas.org> <200401291039.22561.josh@stack.nl> <200402022027.10151.kernel@kolivas.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200402022027.10151.kernel@kolivas.org> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: SpamAssassin 2.60 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Con Kolivas wrote: > What this one does is the following; If there is a "nice" difference > between tasks running on logical cores of the same cpu, the more > "nice" one will run a proportion of time equal to the timeslice it > would have been given relative to the less "nice" task. ie a nice 19 > task running on one core and the nice 0 task running on the other core > will let the nice 0 task run continuously (102ms is normal timeslice) > and the nice 19 task will only run for the last 10ms of time the nice > 0 task is running. This makes for a much more balanced resource > distribution, gives significant preference to the higher priority > task, but allows them to benefit from running on both logical cores. this is a really good rule conceptually - the higher prio task will get at least as much raw (unshared) physical CPU slice as it would get without HT. Ingo