From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 2 Aug 2001 05:27:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 2 Aug 2001 05:27:36 -0400 Received: from rj.sgi.com ([204.94.215.100]:19594 "EHLO rj.corp.sgi.com") by vger.kernel.org with ESMTP id ; Thu, 2 Aug 2001 05:27:27 -0400 Date: Thu, 2 Aug 2001 02:25:48 -0700 (PDT) From: jeremy@classic.engr.sgi.com (Jeremy Higdon) Message-Id: <10108020225.ZM236505@classic.engr.sgi.com> In-Reply-To: Andrea Arcangeli "Re: changes to kiobuf support in 2.4.(?)4" (Aug 2, 11:11am) In-Reply-To: <10108012254.ZM192062@classic.engr.sgi.com> <20010802084259.H29065@athlon.random> <10108020031.ZM229058@classic.engr.sgi.com> <20010802094517.I29065@athlon.random> <10108020110.ZM232959@classic.engr.sgi.com> <20010802102431.L29065@athlon.random> <10108020142.ZM233422@classic.engr.sgi.com> <20010802111150.N29065@athlon.random> X-Mailer: Z-Mail (3.2.3 08feb96 MediaMail) To: Andrea Arcangeli Subject: Re: changes to kiobuf support in 2.4.(?)4 Cc: linux-kernel@vger.kernel.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Aug 2, 11:11am, Andrea Arcangeli wrote: > > > At 13000 IOPS, when allocating and freeing on every I/O request, > > the allocate/free overhead was approximately .6% on a 2 CPU system, > > where the total overhead was about 25%. So I would theoretically > > gain 3% (maybe a little better since there is locking involved) if > > I could avoid the alloc/free. > > Ok good. > > Andrea So one more question for now: Where do I get the O_DIRECT patch? Oh, and is there a plan to get it into 2.4.X? (ok, so two questions) thanks jeremy