From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261583AbVAUQqc (ORCPT ); Fri, 21 Jan 2005 11:46:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261458AbVAUQqD (ORCPT ); Fri, 21 Jan 2005 11:46:03 -0500 Received: from mail20.syd.optusnet.com.au ([211.29.132.201]:64999 "EHLO mail20.syd.optusnet.com.au") by vger.kernel.org with ESMTP id S261523AbVAUQne (ORCPT ); Fri, 21 Jan 2005 11:43:34 -0500 Message-ID: <41F13120.60108@kolivas.org> Date: Sat, 22 Jan 2005 03:43:12 +1100 From: Con Kolivas User-Agent: Mozilla Thunderbird 1.0 (X11/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Marc E. Fiuczynski" Cc: Jens Axboe , Valdis.Kletnieks@vt.edu, Peter Williams , Linux Kernel Mailing List , Chris Han Subject: Re: [ANNOUNCE][RFC] plugsched-2.0 patches ... References: In-Reply-To: X-Enigmail-Version: 0.89.5.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigC18198C247B457F254C5CA1F" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigC18198C247B457F254C5CA1F Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Marc E. Fiuczynski wrote: > Paraphrasing Jens Axboe: > >>I don't think you can compare [plugsched with the plugio framework]. >>Yes they are both schedulers, but that's about where the 'similarity' >>stops. The CPU scheduler must be really fast, overhead must be kept >>to a minimum. For a disk scheduler, we can affort to burn cpu cycles >>to increase the io performance. The extra abstraction required to >>fully modularize the cpu scheduler would come at a non-zero cost as >>well, but I bet it would have a larger impact there. I doubt you >>could measure the difference in the disk scheduler. > > > Modularization usually is done through a level of indirection (function > pointers). I have a can of "indirection be gone" almost ready to spray over > the plugsched framework that would reduce the overhead to zero at runtime. > I'd be happy to finish that work if it makes it more palpable to integrate a > plugsched framework into the kernel? The indirection was a minor point. On modern cpus it was suggested by wli that this would not be a demonstrable hit in perormance. Having said that, I'm sure Peter would be happy for another developer. I know how tiring and lonely it can feel maintaining such a monster. Cheers, Con --------------enigC18198C247B457F254C5CA1F Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFB8TEgZUg7+tp6mRURAjBkAJ9ibaStzeWZW1NaxKx3LD2nJ9v/sgCfTOGT UwyqPJa/KY7nB1KW9mizKnY= =N7Ts -----END PGP SIGNATURE----- --------------enigC18198C247B457F254C5CA1F--