Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 1 Feb 2001 15:56:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 1 Feb 2001 15:56:31 -0500 Received: from sgi.SGI.COM ([192.48.153.1]:8277 "EHLO sgi.com") by vger.kernel.org with ESMTP id ; Thu, 1 Feb 2001 15:56:18 -0500 Message-Id: <200102012056.f11Kulp21108@jen.americas.sgi.com> X-Mailer: exmh version 2.2 06/23/2000 with nmh-1.0.4 To: Christoph Hellwig cc: sct@redhat.com ("Stephen C. Tweedie"), Steve Lord , linux-kernel@vger.kernel.org, "kiobuf-io-devel@lists.sourceforge.net Alan Cox" Subject: Re: [Kiobuf-io-devel] RFC: Kernel mechanism: Compound event wait /notify + callback chains In-Reply-To: Message from Christoph Hellwig of "Thu, 01 Feb 2001 21:33:27 +0100." <200102012033.VAA15590@ns.caldera.de> Date: Thu, 01 Feb 2001 14:56:47 -0600 From: Steve Lord Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > In article <20010201174946.B11607@redhat.com> you wrote: > > Hi, > > > On Thu, Feb 01, 2001 at 05:34:49PM +0000, Alan Cox wrote: > > In the disk IO case, you basically don't get that (the only thing > > which comes close is raid5 parity blocks). The data which the user > > started with is the data sent out on the wire. You do get some > > interesting cases such as soft raid and LVM, or even in the scsi stack > > if you run out of mailbox space, where you need to send only a > > sub-chunk of the input buffer. > > Though your describption is right, I don't think the case is very common: > Sometimes in LVM on a pv boundary and maybe sometimes in the scsi code. And if you are writing to a striped volume via a filesystem which can do it's own I/O clustering, e.g. I throw 500 pages at LVM in one go and LVM is striped on 64K boundaries. Steve - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/