Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423131AbXBBGSQ (ORCPT ); Fri, 2 Feb 2007 01:18:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423133AbXBBGSQ (ORCPT ); Fri, 2 Feb 2007 01:18:16 -0500 Received: from omx1-ext.sgi.com ([192.48.179.11]:44631 "EHLO omx1.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1423131AbXBBGSP (ORCPT ); Fri, 2 Feb 2007 01:18:15 -0500 Date: Thu, 1 Feb 2007 22:17:34 -0800 (PST) From: Christoph Lameter To: Neil Brown cc: Andrew Morton , Ethan Solomita , Paul Menage , linux-kernel@vger.kernel.org, Nick Piggin , linux-mm@kvack.org, Andi Kleen , Paul Jackson , Dave Chinner Subject: Re: [RFC 0/8] Cpuset aware writeback In-Reply-To: <17858.54239.364738.88727@notabene.brown> Message-ID: References: <20070116054743.15358.77287.sendpatchset@schroedinger.engr.sgi.com> <45C2960B.9070907@google.com> <20070201200358.89dd2991.akpm@osdl.org> <17858.54239.364738.88727@notabene.brown> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1063 Lines: 23 On Fri, 2 Feb 2007, Neil Brown wrote: > md/raid doesn't cause any problems here. It preallocates enough to be > sure that it can always make forward progress. In general the entire > block layer from generic_make_request down can always successfully > write a block out in a reasonable amount of time without requiring > kmalloc to succeed (with obvious exceptions like loop and nbd which go > back up to a higher layer). Hmmm... I wonder if that could be generalized. A device driver could make a reservation by increasing min_free_kbytes? Additional drivers in a chain could make additional reservations in such a way that enough memory is set aside for the worst case? > The network stack is of course a different (much harder) problem. An NFS solution is possible without solving the network stack issue? - 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/