From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753942AbcESJF0 (ORCPT ); Thu, 19 May 2016 05:05:26 -0400 Received: from mail-wm0-f43.google.com ([74.125.82.43]:38580 "EHLO mail-wm0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752061AbcESJFY (ORCPT ); Thu, 19 May 2016 05:05:24 -0400 Date: Thu, 19 May 2016 11:05:21 +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 Subject: Re: sharing page cache pages between multiple mappings Message-ID: <20160519090521.GA26114@dhcp22.suse.cz> References: 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 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. [1] https://lwn.net/Articles/684826/ -- Michal Hocko SUSE Labs