From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id 782526B0033 for ; Wed, 27 Sep 2017 09:50:36 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id t69so1552237wmt.7 for ; Wed, 27 Sep 2017 06:50:36 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id w126si3504946wma.171.2017.09.27.06.50.34 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 27 Sep 2017 06:50:35 -0700 (PDT) Date: Wed, 27 Sep 2017 15:50:34 +0200 From: Michal Hocko Subject: Re: [PATCH] mm, swap: Make VMA based swap readahead configurable Message-ID: <20170927135034.yatxlhvunawzmcar@dhcp22.suse.cz> References: <20170921013310.31348-1-ying.huang@intel.com> <20170926132129.dbtr2mof35x4j4og@dhcp22.suse.cz> <20170927050401.GA715@bbox> <20170927074835.37m4dclmew5ecli2@dhcp22.suse.cz> <20170927080432.GA1160@bbox> <20170927083512.dydqlqezh5polggb@dhcp22.suse.cz> <20170927131511.GA338@bgram> <20170927132241.tshup6kcwe5pcxek@dhcp22.suse.cz> <20170927134117.GB338@bgram> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170927134117.GB338@bgram> Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: "Huang, Ying" , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Johannes Weiner , Rik van Riel , Shaohua Li , Hugh Dickins , Fengguang Wu , Tim Chen , Dave Hansen On Wed 27-09-17 22:41:17, Minchan Kim wrote: > On Wed, Sep 27, 2017 at 03:22:41PM +0200, Michal Hocko wrote: [...] > > simply cannot disable swap readahead when page-cluster is 0? > > That's was what I want really but Huang want to use two readahead > algorithms in parallel so he wanted to keep two separated disable > knobs. If it breaks existing and documented behavior then it is a clear regression and it should be fixed. I do not see why this should be disputable at all. Working around an issue with a config option sounds like the wrong way to go because those who cannot do that unconditionally would still see a regression. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org