From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85311C282DA for ; Wed, 17 Apr 2019 15:47:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 552A020656 for ; Wed, 17 Apr 2019 15:47:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732797AbfDQPrW (ORCPT ); Wed, 17 Apr 2019 11:47:22 -0400 Received: from mga12.intel.com ([192.55.52.136]:61296 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732476AbfDQPrW (ORCPT ); Wed, 17 Apr 2019 11:47:22 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Apr 2019 08:43:55 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,362,1549958400"; d="scan'208";a="162731832" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by fmsmga004.fm.intel.com with ESMTP; 17 Apr 2019 08:43:54 -0700 Date: Wed, 17 Apr 2019 09:37:39 -0600 From: Keith Busch To: Michal Hocko Cc: Dave Hansen , Yang Shi , mgorman@techsingularity.net, riel@surriel.com, hannes@cmpxchg.org, akpm@linux-foundation.org, dan.j.williams@intel.com, fengguang.wu@intel.com, fan.du@intel.com, ying.huang@intel.com, ziy@nvidia.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [v2 RFC PATCH 0/9] Another Approach to Use PMEM as NUMA Node Message-ID: <20190417153739.GD4786@localhost.localdomain> References: <1554955019-29472-1-git-send-email-yang.shi@linux.alibaba.com> <20190412084702.GD13373@dhcp22.suse.cz> <20190416074714.GD11561@dhcp22.suse.cz> <876768ad-a63a-99c3-59de-458403f008c4@linux.alibaba.com> <20190417092318.GG655@dhcp22.suse.cz> <20190417152345.GB4786@localhost.localdomain> <20190417153923.GO5878@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190417153923.GO5878@dhcp22.suse.cz> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 17, 2019 at 05:39:23PM +0200, Michal Hocko wrote: > On Wed 17-04-19 09:23:46, Keith Busch wrote: > > On Wed, Apr 17, 2019 at 11:23:18AM +0200, Michal Hocko wrote: > > > On Tue 16-04-19 14:22:33, Dave Hansen wrote: > > > > Keith Busch had a set of patches to let you specify the demotion order > > > > via sysfs for fun. The rules we came up with were: > > > > > > I am not a fan of any sysfs "fun" > > > > I'm hung up on the user facing interface, but there should be some way a > > user decides if a memory node is or is not a migrate target, right? > > Why? Or to put it differently, why do we have to start with a user > interface at this stage when we actually barely have any real usecases > out there? The use case is an alternative to swap, right? The user has to decide which storage is the swap target, so operating in the same spirit.