From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: Re: [PATCH 7/9] scsi_dh: Add support for SDEV_PASSIVE Date: Mon, 11 Feb 2008 12:18:00 -0700 Message-ID: <20080211191800.GO5299@parisc-linux.org> References: <20080124003010.18871.84095.sendpatchset@localhost.localdomain> <20080124003203.18871.52040.sendpatchset@localhost.localdomain> <1202151498.3096.84.camel@localhost.localdomain> <1202156151.13537.14.camel@linuxchandra> <1202156914.3096.112.camel@localhost.localdomain> <1202159970.13537.19.camel@linuxchandra> <20080209124511.GB28967@parisc-linux.org> <1202754466.13537.123.camel@linuxchandra> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from palinux.external.hp.com ([192.25.206.14]:34710 "EHLO mail.parisc-linux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752074AbYBKTSD (ORCPT ); Mon, 11 Feb 2008 14:18:03 -0500 Content-Disposition: inline In-Reply-To: <1202754466.13537.123.camel@linuxchandra> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Chandra Seetharaman Cc: James Bottomley , dm-devel@redhat.com, linux-scsi@vger.kernel.org, Mike Anderson , michaelc@cs.wisc.edu, jens.axboe@oracle.com On Mon, Feb 11, 2008 at 10:27:46AM -0800, Chandra Seetharaman wrote: > On Sat, 2008-02-09 at 05:45 -0700, Matthew Wilcox wrote: > > On Mon, Feb 04, 2008 at 01:19:30PM -0800, Chandra Seetharaman wrote: > > > The device does send these error messages currently, but it takes some > > > time to get the check condition back, which adds up the time to boot > > > especially when the # of LUNS is huge. > > > > > > For example, in my test configuration, I had 40 luns, and the time > > > difference (with this patch and without it) to boot is 171 seconds and > > > 1426 seconds. > > > > Was that with sync or async SCSI bus scanning? > > I didn't change anything, IOW, i did default scanning, which I would > guess sync ?! That would depend on your CONFIG_SCSI_SCAN_ASYNC setting. Try booting with 'scsi_mod.scan=async' and without this patch, and see how long it takes. -- Intel are signing my paycheques ... these opinions are still mine "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."