From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754442AbcESKxd (ORCPT ); Thu, 19 May 2016 06:53:33 -0400 Received: from mail-wm0-f46.google.com ([74.125.82.46]:37687 "EHLO mail-wm0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754232AbcESKxb (ORCPT ); Thu, 19 May 2016 06:53:31 -0400 Date: Thu, 19 May 2016 12:53:28 +0200 From: Michal Hocko To: Miklos Szeredi Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, "Darrick J. Wong" Subject: Re: sharing page cache pages between multiple mappings Message-ID: <20160519105328.GJ26110@dhcp22.suse.cz> References: <20160519090521.GA26114@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 19-05-16 12:17:14, Miklos Szeredi wrote: > On Thu, May 19, 2016 at 11:05 AM, Michal Hocko wrote: > > On Thu 19-05-16 10:20:13, Miklos Szeredi wrote: > >> Has anyone thought about sharing pages between multiple files? > >> > >> The obvious application is for COW filesytems where there are > >> logically distinct files that physically share data and could easily > >> share the cache as well if there was infrastructure for it. > > > > FYI this has been discussed at LSFMM this year[1]. I wasn't at the > > session so cannot tell you any details but the LWN article covers it at > > least briefly. > > Cool, so it's not such a crazy idea. FWIW it is ;) -- Michal Hocko SUSE Labs