Return-Path: <linux-kernel-owner+willy=40w.ods.org@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S261943AbUC1AGj (ORCPT <rfc822;willy@w.ods.org>);
	Sat, 27 Mar 2004 19:06:39 -0500
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261987AbUC1AGZ
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Sat, 27 Mar 2004 19:06:25 -0500
Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:20149 "EHLO
	www.linux.org.uk") by vger.kernel.org with ESMTP id S261979AbUC1AGT
	(ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Sat, 27 Mar 2004 19:06:19 -0500
Message-ID: <406616EE.80301@pobox.com>
Date: Sat, 27 Mar 2004 19:06:06 -0500
From: Jeff Garzik <jgarzik@pobox.com>
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703
X-Accept-Language: en-us, en
MIME-Version: 1.0
To: Nick Piggin <nickpiggin@yahoo.com.au>
CC: linux-ide@vger.kernel.org, Linux Kernel <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] speed up SATA
References: <4066021A.20308@pobox.com> <40661049.1050004@yahoo.com.au> <406611CA.3050804@pobox.com>
In-Reply-To: <406611CA.3050804@pobox.com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 938
Lines: 28

Jeff Garzik wrote:
> It's up to the sysadmin to choose a disk scheduling policy they like, 
> which implies that a _scheduler_, not each individual driver, should 
> place policy limitations on max_sectors.


<tangent>

The block layer / scheduler guys should also think about a general (not 
SCSI specific) way to tune TCQ tag depth.  That's IMO another policy 
decision.

I'm about to add a raft of SATA-2 hardware, all of which are queued. 
The standard depth is 32, but one board supports a whopping depth of 256.

Given past discussion on the topic, you probably don't want to queue 256 
requests at a time to hardware :)  But the sysadmin should be allowed 
to, if they wish...

	Jeff



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/