From mboxrd@z Thu Jan 1 00:00:00 1970 From: Timothy Miller Subject: Re: [PATCH] speed up SATA Date: Tue, 30 Mar 2004 13:05:44 -0500 Sender: linux-ide-owner@vger.kernel.org Message-ID: <4069B6F8.1020506@techsource.com> References: <4066021A.20308@pobox.com> <200403282030.11743.bzolnier@elka.pw.edu.pl> <20040328183010.GQ24370@suse.de> <200403282045.07246.bzolnier@elka.pw.edu.pl> <406720A7.1050501@pobox.com> <20040329005502.GG3039@dualathlon.random> <40679FE3.3080007@pobox.com> <20040329130410.GH3039@dualathlon.random> <40687CF0.3040206@pobox.com> <20040330110928.GR24370@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from kinesis.swishmail.com ([209.10.110.86]:26643 "EHLO kinesis.swishmail.com") by vger.kernel.org with ESMTP id S263777AbUC3Rqo (ORCPT ); Tue, 30 Mar 2004 12:46:44 -0500 In-Reply-To: <20040330110928.GR24370@suse.de> List-Id: linux-ide@vger.kernel.org To: Jens Axboe Cc: Jeff Garzik , Andrea Arcangeli , Bartlomiej Zolnierkiewicz , William Lee Irwin III , Nick Piggin , linux-ide@vger.kernel.org, Linux Kernel , Andrew Morton Jens Axboe wrote: > - The optimal_sectors calculation is just an average of previous maximum > with current maximum. The scheme has a number of break down points, > for instance writes starving reads will give you a bad read execution > time, further limiting ->optimal_sectors[READ] I did look through your code a bit, but one thing to be concerned with is that going only on max throughput might be fooled by cache hits on the drive.