Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261721AbVEPPoy (ORCPT ); Mon, 16 May 2005 11:44:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261712AbVEPPn0 (ORCPT ); Mon, 16 May 2005 11:43:26 -0400 Received: from pop.gmx.net ([213.165.64.20]:53459 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S261725AbVEPPkf (ORCPT ); Mon, 16 May 2005 11:40:35 -0400 X-Authenticated: #428038 Date: Mon, 16 May 2005 17:40:20 +0200 From: Matthias Andree To: Alan Cox Cc: Matthias Andree , Arjan van de Ven , Linux Kernel Mailing List Subject: Re: Linux does not care for data integrity (was: Disk write cache) Message-ID: <20050516154020.GD949@merlin.emma.line.org> Mail-Followup-To: Alan Cox , Arjan van de Ven , Linux Kernel Mailing List References: <200505151121.36243.gene.heskett@verizon.net> <20050515152956.GA25143@havoc.gtf.org> <20050516.012740.93615022.okuyamak@dd.iij4u.or.jp> <42877C1B.2030008@pobox.com> <20050516110203.GA13387@merlin.emma.line.org> <1116241957.6274.36.camel@laptopd505.fenrus.org> <20050516112956.GC13387@merlin.emma.line.org> <1116252157.6274.41.camel@laptopd505.fenrus.org> <20050516144831.GA949@merlin.emma.line.org> <1116256005.21388.55.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1116256005.21388.55.camel@localhost.localdomain> X-PGP-Key: http://home.pages.de/~mandree/keys/GPGKEY.asc User-Agent: Mutt/1.5.9i X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1817 Lines: 41 On Mon, 16 May 2005, Alan Cox wrote: > I'd prefer Linux turned writecache off on old drives but Mark Lord has > really good points even there. And for scsi we do tagging and the > journals can be ordered depending on your need. Is tagged command queueing (we'll need the ordered tag here) compatible with all SCSI adaptors that Linux supports? What if tagged command queueing is switched off for some reason (adaptor or HW incapability, user override) and the drive still has write cache enable = true and queue algorithm modifier = 1 (which permits out-of-order execution of write requests except for ordered tags)? Is that something that would cause some bit of notice to be logged? Or is that simply "do this at your own risk". My recent SCSI drives have been shipping with WCE=1 and QAM=0. Am I missing a bit here? > You also appear confused: It isn't the maintainers responsibility to > arrange for such info. It's the maintainers responsibility to process > contributed patches with such info. I didn't think of arranging as in "write himself". Who writes that info down doesn't matter, but I'd think that such documentation should always be committed alongside the code, except in code marked experimental. (which, in turn, should only be promoted to non-experimental if it's properly documented). I understand that people who understand the code are eager to focus on the code and even if that documentation is just an unordered lists of statement with a kernel version attached, that'd be fine. But what is a decent code without users? -- Matthias Andree - 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/