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,URIBL_BLOCKED,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 08CACC43387 for ; Thu, 17 Jan 2019 16:48:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CAA05205C9 for ; Thu, 17 Jan 2019 16:48:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729124AbfAQQs4 (ORCPT ); Thu, 17 Jan 2019 11:48:56 -0500 Received: from mga17.intel.com ([192.55.52.151]:11152 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728980AbfAQQsv (ORCPT ); Thu, 17 Jan 2019 11:48:51 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Jan 2019 08:48:50 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,489,1539673200"; d="scan'208";a="119296606" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by orsmga003.jf.intel.com with ESMTP; 17 Jan 2019 08:48:49 -0800 Date: Thu, 17 Jan 2019 09:47:37 -0700 From: Keith Busch To: Jeff Moyer Cc: Dave Hansen , thomas.lendacky@amd.com, fengguang.wu@intel.com, dave@sr71.net, linux-nvdimm@lists.01.org, tiwai@suse.de, zwisler@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.com, baiyaowei@cmss.chinamobile.com, ying.huang@intel.com, bhelgaas@google.com, akpm@linux-foundation.org, bp@suse.de Subject: Re: [PATCH 0/4] Allow persistent memory to be used like normal RAM Message-ID: <20190117164736.GC31543@localhost.localdomain> References: <20190116181859.D1504459@viggo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Thu, Jan 17, 2019 at 11:29:10AM -0500, Jeff Moyer wrote: > Dave Hansen writes: > > Persistent memory is cool. But, currently, you have to rewrite > > your applications to use it. Wouldn't it be cool if you could > > just have it show up in your system like normal RAM and get to > > it like a slow blob of memory? Well... have I got the patch > > series for you! > > So, isn't that what memory mode is for? > https://itpeernetwork.intel.com/intel-optane-dc-persistent-memory-operating-modes/ > > Why do we need this code in the kernel? I don't think those are the same thing. The "memory mode" in the link refers to platforms that sequester DRAM to side cache memory access, where this series doesn't have that platform dependency nor hides faster DRAM.