From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Wilck Subject: Re: [PATCH] scsi/mptsas: add RAID devices in ascending ID order Date: Mon, 25 Sep 2006 11:59:29 +0200 Message-ID: <4517A881.3000903@fujitsu-siemens.com> References: <664A4EBB07F29743873A87CF62C26D7032D5CF@NAMAIL4.ad.lsil.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from dgate2.fujitsu-siemens.com ([217.115.66.36]:8847 "EHLO dgate2.fujitsu-siemens.com") by vger.kernel.org with ESMTP id S1750897AbWIYJ7h (ORCPT ); Mon, 25 Sep 2006 05:59:37 -0400 In-Reply-To: <664A4EBB07F29743873A87CF62C26D7032D5CF@NAMAIL4.ad.lsil.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Moore, Eric" Cc: linux-scsi@vger.kernel.org, mpt_linux_developer Hi Eric, thanks for your response. >> The patch makes sure that arrays are added in ascending >> VolumeID order. > > Rejected. > > Ascending ID ordering does not address all cases. > There is no guarantee which target ids are > assigned by firmware to volumes when > volumes are created. That's what my patch was supposed to handle: No matter what the ordering of IDs by firmware is, the devices are registered in ascending ID order. > I've made similar > ordering proposals before to this mailing list. > All been rejected. Do you have a thread reference for me? I'd like to understand the arguments better. I find this strange because scanning in ascending order has always been the common case in drivers as well as in the mid layer, AFAIK. > I suggest that you not map your devices > to /dev/sda, but instead use persistent > device labels or names. Most distro's > now days ship with Logical Volume Manager > that does this for you. I know it. The problem is that there are important distros out there that do support persistent device names and LVM, but don't enable them by default. My patch was intended to implement the "principle of least surprise" for users of such distributions with little experience. More so because mptspi and mptsas behave differently; the problem I was talking about is currently only encountered with mptsas. Regards, Martin -- Martin Wilck Phone: +49 5251 8 15113 Fujitsu Siemens Computers Fax: +49 5251 8 20409 Heinz-Nixdorf-Ring 1 mailto:Martin.Wilck@Fujitsu-Siemens.com D-33106 Paderborn http://www.fujitsu-siemens.com/primergy