From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: kernel 2.6.31.1 + Sil 3512 + WDC WD5000AAKS-00V1A0 = no NCQ and UDMA5 instead of UDMA6 Date: Thu, 17 Dec 2009 22:10:58 -0500 Message-ID: <4B2AF2C2.9010708@pobox.com> References: <4B2A3D25.9030209@hardwarefreak.com> <4B2A720B.2040809@pobox.com> <4B2AE779.9060109@hardwarefreak.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-yx0-f187.google.com ([209.85.210.187]:40517 "EHLO mail-yx0-f187.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752787AbZLRDLC (ORCPT ); Thu, 17 Dec 2009 22:11:02 -0500 Received: by yxe17 with SMTP id 17so2556137yxe.33 for ; Thu, 17 Dec 2009 19:11:01 -0800 (PST) In-Reply-To: <4B2AE779.9060109@hardwarefreak.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Stan Hoeppner Cc: linux-ide@vger.kernel.org On 12/17/2009 09:22 PM, Stan Hoeppner wrote: > Jeff Garzik put forth on 12/17/2009 12:01 PM: >> On 12/17/2009 09:16 AM, Stan Hoeppner wrote: >>> Hi Jeff, >>> >>> I recently added a Silicon Image 3512 based PCI card to an old Intel >>> 440BX machine along with a single platter 500GB WD SATA2 drive. I'd >>> have gone with an ahci sata2 controller but couldn't find one in 33MHz >>> PCI. I compiled a new kernel, adding SCSI disk, libata and sata_sil >>> support using make menuconfig and kernel.org sources installed the >>> debian way on lenny 5.0.3. I left the old piix diver in so I could >>> still boot from the old IDE disk and move the entire Linux system over. >>> That all went pretty smoothly, I'm now booting from the new disk, and >>> the sata subsystem is working pretty well, especially compared to the >>> old 40GB Maxtor IDE disk (now removed from the system). >> >> sata_sil hardware does not support NCQ. >> >> Jeff > > Dangit, I thought the 3512 was one of the SiI chips that did support it. > My mistake. Is there anything else I can tweak to get more of this > drive's performance or am I stuck with what I have? My read of your > default UDMA/100 comments is that it's a safety net type setting for the > 3112. Would bumping this to UDMA/133 give me any improvement over the > PCI bus? Is there anything else I could tweak? Nope. You are pretty much maxing out the drive, of whatever drive you plug in. The sata bus -- at its hardware spec'd maximum -- is far faster than just about any drive, and the PCI bus is far faster than the sata bus. You could probably max out the SATA bus with a RAM-based SATA device; that's it. Jeff