From mboxrd@z Thu Jan 1 00:00:00 1970 From: Timothy Miller Subject: Re: [PATCH] speed up SATA Date: Tue, 30 Mar 2004 13:19:39 -0500 Sender: linux-ide-owner@vger.kernel.org Message-ID: <4069BA3B.5050004@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> <4069B6F8.1020506@techsource.com> <4069B376.9010104@pobox.com> 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]:51717 "EHLO kinesis.swishmail.com") by vger.kernel.org with ESMTP id S263779AbUC3SAj (ORCPT ); Tue, 30 Mar 2004 13:00:39 -0500 In-Reply-To: <4069B376.9010104@pobox.com> List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Jens Axboe , Andrea Arcangeli , Bartlomiej Zolnierkiewicz , William Lee Irwin III , Nick Piggin , linux-ide@vger.kernel.org, Linux Kernel , Andrew Morton Jeff Garzik wrote: > > > > If you are taking your samples over time, that shouldn't matter... if > the system workload is such that you are hitting the drive cache the > majority of the time, you're not being "fooled" by cache hits, the patch > would be taking those cache hits into account. > > If the system isn't hitting the drive cache the majority of the time, > statistical sampling will automatically notice that too... > I completely agree, although Jens' patch seems to try to learn the drive's maximum speed and go based on that. Maybe I misread the code. Anyhow, it's certainly excellent for a starting point... it's this sort of proof-of-concept that gets the ball rolling. Plus, it's already better than Jens says it is. :)