From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756569Ab1GGM6k (ORCPT ); Thu, 7 Jul 2011 08:58:40 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:56074 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756516Ab1GGM6h (ORCPT ); Thu, 7 Jul 2011 08:58:37 -0400 Date: Thu, 7 Jul 2011 08:58:31 -0400 From: Christoph Hellwig To: Mel Gorman Cc: Andrew Morton , Linux-MM , Linux-Netdev , LKML , David Miller , Neil Brown , Peter Zijlstra Subject: Re: [PATCH 00/14] Swap-over-NBD without deadlocking v5 Message-ID: <20110707125831.GA15412@infradead.org> References: <1308575540-25219-1-git-send-email-mgorman@suse.de> <20110706165146.be7ab61b.akpm@linux-foundation.org> <20110707094737.GG15285@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110707094737.GG15285@suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 07, 2011 at 10:47:37AM +0100, Mel Gorman wrote: > Additional complexity is required for swap-over-NFS but affects the > core kernel far less than this series. I do not have a series prepared > but from what's in a distro kernel, supporting NFS requires extending > address_space_operations for swapfile activation/deactivation with > some minor helpers and the bulk of the remaining complexity within > NFS itself. The biggest addition for swap over NFS is to add proper support for a filesystem interface to do I/O on random kernel pages instead of the current nasty bmap hack the swapfile code is using. Splitting that work from all the required VM infrastructure should make life easier for everyone involved and allows merging it independeny as both bits have other uses case as well.