From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 4/4] sata_sil: implement Mod15Write workaround by split request processing Date: Tue, 31 Oct 2006 20:59:50 -0500 Message-ID: <4547FF96.4070808@pobox.com> References: <11612370993859-git-send-email-htejun@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:12757 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S1946372AbWKAB7x (ORCPT ); Tue, 31 Oct 2006 20:59:53 -0500 In-Reply-To: <11612370993859-git-send-email-htejun@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: linux-ide@vger.kernel.org Tejun Heo wrote: > Instead of limiting max_sectors to 15 unconditionally, this patch > leaves max_sectors at the default value and process write requests > larger than 15 sectors by processing them in <= 15 sectors chunks. > This results in unhamplered read performance and better write > performance. > > Split request processing is performed only for DMA write requests > 15 > sectors. dev->max_sectors is limited to 15 sectors when the device is > put into PIO mode. > > Signed-off-by: Tejun Heo I'm still put off by the complexity that this adds to each transfer, and to the overall driver itself. It's largely older chips and drives, so I don't think it's worth carrying this code for decades to come, just for some early SATA screwups.