Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 16 Nov 2002 03:11:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 16 Nov 2002 03:11:32 -0500 Received: from ns.virtualhost.dk ([195.184.98.160]:49594 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id ; Sat, 16 Nov 2002 03:11:31 -0500 Date: Sat, 16 Nov 2002 09:18:28 +0100 From: Jens Axboe To: Steve Lord Cc: Linux Kernel Subject: Re: SCSI I/O performance problems when CONFIG_HIGHIO is off Message-ID: <20021116081828.GB8495@suse.de> References: <1037392310.13531.419.camel@jen.americas.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1037392310.13531.419.camel@jen.americas.sgi.com> User-Agent: Mutt/1.4i X-OS: Linux 2.4.20-pre10 i686 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1021 Lines: 31 On Fri, Nov 15 2002, Steve Lord wrote: > Jens, > > As you know, for the last week or so I have been battling some > performance issues in XFS and 2.4.20-rc1. Well, we finally found > the culprit back in 2.4.20-pre2. > > When the block highmem patch was included, it added highmem_io to the > scsi controller structure. This can only ever be set to one if > CONFIG_HIGHIO is set. Yet there are several spots in the scsi > code which test based on its value regardless. Doh! You are right, this is a very stupid bug, thanks for catching it. I'm on the road this weekend, I'' submit a patch to fix it as soon as I get back. > Jens, can you do something about this please? Of course > p.s. You now owe me a week's consulting some time ;-) Indeed, sorry about that... Jens - 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/