From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f199.google.com (mail-qt0-f199.google.com [209.85.216.199]) by kanga.kvack.org (Postfix) with ESMTP id E6C556B0253 for ; Fri, 6 Oct 2017 08:29:01 -0400 (EDT) Received: by mail-qt0-f199.google.com with SMTP id k56so9004746qtc.1 for ; Fri, 06 Oct 2017 05:29:01 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id y9sor928278qkl.49.2017.10.06.05.29.00 for (Google Transport Security); Fri, 06 Oct 2017 05:29:00 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20171002144903.d58ed6887adfd9dc4cdfd697@linux-foundation.org> References: <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> <20170927135034.yatxlhvunawzmcar@dhcp22.suse.cz> <20170927141008.GA1278@bgram> <20170927141723.bixcum3fler7q4w5@dhcp22.suse.cz> <87mv5f8wkj.fsf@yhuang-dev.intel.com> <20171002144903.d58ed6887adfd9dc4cdfd697@linux-foundation.org> From: huang ying Date: Fri, 6 Oct 2017 20:28:59 +0800 Message-ID: Subject: Re: [PATCH] mm, swap: Make VMA based swap readahead configurable Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Dave Hansen , "Huang, Ying" , Michal Hocko , Minchan Kim , linux-mm@kvack.org, LKML , Johannes Weiner , Rik van Riel , Shaohua Li , Hugh Dickins , Fengguang Wu , Tim Chen On Tue, Oct 3, 2017 at 5:49 AM, Andrew Morton wrote: > On Mon, 2 Oct 2017 08:45:40 -0700 Dave Hansen wrote: > >> On 09/27/2017 06:02 PM, Huang, Ying wrote: >> > I still think there may be a performance regression for some users >> > because of the change of the algorithm and the knobs, and the >> > performance regression can be resolved via setting the new knob. But I >> > don't think there will be a functionality regression. Do you agree? >> >> A performance regression is a regression. I don't understand why we are >> splitting hairs as to what kind of regression it is. >> > > Yes. > > Ying, please find us a way of avoiding any disruption to existing > system setups. One which doesn't require that the operator perform a > configuration change to restore prior behaviour/performance. Sorry for late. I am in holiday recently. OK. For me, I think the most clean way is to use page_cluster to control both the virtual and physical swap readahead. If you are OK with that, I will prepare the patch. > And please let's get this done well in advance of the 4.14 release. Sure. Best Regards, Huang, Ying -- 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