From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian King Subject: Re: [PATCH 1/1] scsi: Add allow_restart sysfs class attribute Date: Tue, 27 Jun 2006 14:54:43 -0500 Message-ID: <44A18D03.4080705@us.ibm.com> References: <200606271610.k5RGAXcT005333@d03av04.boulder.ibm.com> <44A18AF7.7000504@s5r6.in-berlin.de> Reply-To: brking@us.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from e1.ny.us.ibm.com ([32.97.182.141]:19630 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id S932552AbWF0Tys (ORCPT ); Tue, 27 Jun 2006 15:54:48 -0400 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e1.ny.us.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id k5RJslna018580 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Tue, 27 Jun 2006 15:54:47 -0400 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay02.pok.ibm.com (8.13.6/NCO/VER7.0) with ESMTP id k5RJslYH271506 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Tue, 27 Jun 2006 15:54:47 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id k5RJsknq030518 for ; Tue, 27 Jun 2006 15:54:47 -0400 In-Reply-To: <44A18AF7.7000504@s5r6.in-berlin.de> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Stefan Richter Cc: James.Bottomley@steeleye.com, linux-scsi@vger.kernel.org, parasietje@gmail.com Stefan Richter wrote: > Brian King wrote: >> This is a resend of a patch I generated in response to an email sent >> by Ruben Faelens . His original email to >> linux-scsi requested a method in which he could spin down a scsi disk >> when not in use and have the kernel automatically spin it back up when >> an I/O was generated to the disk. The infrastructure to automatically >> spin a disk up has been in the scsi error handler for some time now, > > I am positively surprised that this code is actually already there --- I > didn't notice... > >> but it is not enabled by default. This patch adds an sd sysfs attribute >> which allows userspace to enable this behavior. > > What is the reason that the code is not enabled by default? Are there > dependencies on command set or transport, or firmwares which won't react > properly? There was concern when the patch went in that if it was enabled by default it would break a bunch of USB devices. http://marc.theaimsgroup.com/?l=linux-scsi&m=107702811830956&w=2 -- Brian King eServer Storage I/O IBM Linux Technology Center