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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 1F6DDC54FC9 for ; Mon, 20 Apr 2020 02:32:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00D812076B for ; Mon, 20 Apr 2020 02:32:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726117AbgDTCc6 (ORCPT ); Sun, 19 Apr 2020 22:32:58 -0400 Received: from mga03.intel.com ([134.134.136.65]:20233 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726083AbgDTCc5 (ORCPT ); Sun, 19 Apr 2020 22:32:57 -0400 IronPort-SDR: 8B/KEnNtY3CoaqCvvopdSmeKlHNAHeXpyUqJ5fhxl6iHtY88GUjylId4a1bfJnKoBrtrmCQxjE e8Klx+Vnxq4A== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Apr 2020 19:32:57 -0700 IronPort-SDR: CSVLQz9oXuocuFRvUvZLxSkA5EA1wVP/y9a1uB6hCn7SceHMo+m5DghLzVubub3hZrBGu7MpHM gthpS6iHBU3g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,405,1580803200"; d="scan'208";a="279092743" Received: from yhuang-dev.sh.intel.com (HELO yhuang-dev) ([10.239.159.23]) by fmsmga004.fm.intel.com with ESMTP; 19 Apr 2020 19:32:54 -0700 From: "Huang\, Ying" To: SeongJae Park Cc: Mel Gorman , SeongJae Park , Mel Gorman , Peter Zijlstra , , , Ingo Molnar , Rik van Riel , Daniel Jordan , Tejun Heo , Dave Hansen , Tim Chen , Aubrey Li Subject: Re: [RFC] autonuma: Support to scan page table asynchronously References: <20200418094811.4757-1-sj38.park@gmail.com> Date: Mon, 20 Apr 2020 10:32:53 +0800 In-Reply-To: <20200418094811.4757-1-sj38.park@gmail.com> (SeongJae Park's message of "Sat, 18 Apr 2020 11:48:11 +0200") Message-ID: <877dyaubsa.fsf@yhuang-dev.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SeongJae Park writes: > > DAMON allows users to know which address ranges have which access frequency. > Thus, I think DAMON could be used for detection of hot pages, which will be > good migration candidates, instead of the NUMA hinting fault based referenced > pages detection. > > The benefits I expect from this change are better accuracy and less overhead. > As we can know not only referenced pages but hot pages, migration will be more > effective. The purpose of AutoNUMA scanning isn't to find the hot pages, but the pages that are accessed across NUMA node. PTE accessed bit cannot provide information of accessing CPU, so it's not enough for AutoNUMA. Best Regards, Huang, Ying