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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 F14E2C10F03 for ; Thu, 25 Apr 2019 06:37:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA8BE217D7 for ; Thu, 25 Apr 2019 06:37:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556174251; bh=Vrm4AJrU0Dcl/sGJwB8cHfS3aOvJp5LOZPssLzieaV4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=OS4R66LOL53tb7MQ0lnv6FKnPG/91oupT1la/datydKt5TNot3Ge6TZ5sdt1VRq6w XaKbKe5DI8lwTXAeN23HLPmRQEsVShnI5HgPJSJsDBA+bhlFHiiWlKCmDvAmpr3kgL +xk1oBaoJTgKW/63qFXJ69EmjDswjtybduMNAIIo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729729AbfDYGha (ORCPT ); Thu, 25 Apr 2019 02:37:30 -0400 Received: from mx2.suse.de ([195.135.220.15]:55864 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727128AbfDYGha (ORCPT ); Thu, 25 Apr 2019 02:37:30 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 5232FAE5E; Thu, 25 Apr 2019 06:37:28 +0000 (UTC) Date: Thu, 25 Apr 2019 08:37:27 +0200 From: Michal Hocko To: Fan Du Cc: akpm@linux-foundation.org, fengguang.wu@intel.com, dan.j.williams@intel.com, dave.hansen@intel.com, xishi.qiuxishi@alibaba-inc.com, ying.huang@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 0/5] New fallback workflow for heterogeneous memory system Message-ID: <20190425063727.GJ12751@dhcp22.suse.cz> References: <1556155295-77723-1-git-send-email-fan.du@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1556155295-77723-1-git-send-email-fan.du@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 25-04-19 09:21:30, Fan Du wrote: [...] > However PMEM has different characteristics from DRAM, > the more reasonable or desirable fallback style would be: > DRAM node 0 -> DRAM node 1 -> PMEM node 2 -> PMEM node 3. > When DRAM is exhausted, try PMEM then. Why and who does care? NUMA is fundamentally about memory nodes with different access characteristics so why is PMEM any special? -- Michal Hocko SUSE Labs