Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 9 Dec 2001 18:33:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 9 Dec 2001 18:32:51 -0500 Received: from e21.nc.us.ibm.com ([32.97.136.227]:19075 "EHLO e21.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Sun, 9 Dec 2001 18:32:35 -0500 Date: Sun, 9 Dec 2001 14:31:52 -0800 From: Mike Kravetz To: Alan Cox Cc: Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH] 2.5.0 Multi-Queue Scheduler Message-ID: <20011209143152.A1087@w-mikek2.sequent.com> In-Reply-To: <20011207143415.B1127@w-mikek2.des.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from alan@lxorguk.ukuu.org.uk on Sat, Dec 08, 2001 at 11:58:22AM +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 08, 2001 at 11:58:22AM +0000, Alan Cox wrote: > Which version of the scheduler do you behave like ? The 'current'. In this case 2.5.0. This work was mostly interested in changing data structure layout and algorithms used to make scheduling decisions. We still wanted to make the same decision, just more efficiently when faced with a high rate of scheduling decisions or large number of runnable tasks. Like I said earlier, this design constraint was both good and bad. > I have the core bits of a scheduler that behaves roughly like Linux 2.4 with > the recent Ingo cache change [in fact that came from working out what the > Linus scheduler does]. > > Uniprocessor scheduling is working fine (I've not tackled the RT stuff tho) > SMP I'm pondering bits still. > > Currently I do the following > > Two sets of 8 queues per processor, and a bitmask of non empty queues. I assume the queue a task is assigned to is based on its priority? Or am I way off. Are there 8 ranges of priorities for runnable tasks? Just curious how you came up with 8. We also dabbled with a scheduler that had queues based on task priority. One issue was that we couldn't seem to come up with an optimal number of queues to represent all task priorities. -- Mike - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/