Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932428AbWJEXdf (ORCPT ); Thu, 5 Oct 2006 19:33:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932429AbWJEXdf (ORCPT ); Thu, 5 Oct 2006 19:33:35 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:41695 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S932428AbWJEXde (ORCPT ); Thu, 5 Oct 2006 19:33:34 -0400 Message-ID: <45259679.7050804@torque.net> Date: Thu, 05 Oct 2006 19:34:17 -0400 From: Douglas Gilbert Reply-To: dougg@torque.net User-Agent: Thunderbird 1.5.0.4 (X11/20060614) MIME-Version: 1.0 To: Guennadi Liakhovetski CC: Jeff Garzik , James Bottomley , Linus Torvalds , Andrew Morton , linux-kernel , linux-scsi Subject: Re: [GIT PATCH] scsi updates for post 2.6.18 References: <1159995678.3437.80.camel@mulgrave.il.steeleye.com> <45255A02.2010308@garzik.org> In-Reply-To: X-Enigmail-Version: 0.94.0.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2407 Lines: 67 Guennadi Liakhovetski wrote: > On Thu, 5 Oct 2006, Jeff Garzik wrote: > >> Guennadi Liakhovetski wrote: >>> On Wed, 4 Oct 2006, James Bottomley wrote: >>> >>>> This is (hopefully) my final batch of updates before we go -rc1. It's >>>> mainly code cleanups, some driver updates and the new qla4xxx iScsi >>>> driver. >>> James, is there a reason why you didn't include this one: >>> >>> http://marc.theaimsgroup.com/?l=linux-scsi&m=115974328128341&w=2 >>> >>> Do you think it can cause problems? >> It would be nice to get it tested, based on your "don't know if it works >> though" comment... > > Sure, it WOULD be nice, but I don't know how. The "don't know" refers to > the case 16MB block size, my tape supports only 16MB - 1 byte (according > to st report). Is there a way to test various block sizes with CDs / > hard-disks / ZIP / scanners? > Would something with sg_dd work? Interesting challenge. In lk 2.6.19-rc1 with /dev/sda and /dev/sg0 the same SCSI disk I can get close: [root@sas parameters]# cd /sys/block/sda/queue/ [root@sas queue]# echo 32767 > max_sectors_kb [root@sas queue]# cd /sys/module/sg/parameters/ [root@sas parameters]# echo 131072 > scatter_elem_sz [root@sas parameters]# sg_dd if=/dev/sg0 of=/dev/null bs=512 bpt=32640 count=32k verbose=3 >> Input file type: SCSI generic (sg) device open input(sg_io), flags=0x800 inquiry cdb: 12 00 00 00 24 00 /dev/sg0: SEAGATE ST336754SS 0003 [pdt=0] >> Output file type: null device read cdb: 28 00 00 00 00 00 00 7f 80 00 duration=180 ms read cdb: 28 00 00 00 7f 80 00 00 80 00 duration=4 ms 32768+0 records in 32768+0 records out So I got within 128 (512 byte) sectors of a 16 MB transfer on a single command. Hmm. This is with a adaptec 48300 HBA with the aic94xx driver (take your pick which one). Looks like > it must be only sector size. Can I low-level format a disk with 16M > sector?:-) No usually. Some SCSI disk can be formatted up to 528 byte sectors but that is a long way short. > Another possibility is to limit the block size at 8MB - I can test that. The sg driver gets around that in lk 2.6.19-rc1 Doug Gilbert - 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/