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[23.128.96.19]) by mx.google.com with ESMTPS id d1si1015705pgm.782.2022.02.23.16.44.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Feb 2022 16:44:59 -0800 (PST) Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19; Authentication-Results: mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=UZmRO4wP; spf=softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 550C7D0493; Wed, 23 Feb 2022 16:41:45 -0800 (PST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245131AbiBXAGh (ORCPT + 99 others); Wed, 23 Feb 2022 19:06:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239487AbiBXAGg (ORCPT ); Wed, 23 Feb 2022 19:06:36 -0500 Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B253558380 for ; Wed, 23 Feb 2022 16:06:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645661164; x=1677197164; h=message-id:date:mime-version:to:cc:references:from: subject:in-reply-to:content-transfer-encoding; bh=Uu+jTVal72wWHq+zRSDpCjRHJopUoZhOIPfQFDisbtU=; b=UZmRO4wP5INCTYApUxIveaRquM5lsq6ho+icEkZ0kn4zOPjcAQcFQqWZ +fvfFQ5uESqJLjnwITl1NQ+BM8YxAhnIkyjZuI9L63AuB7v2EFExFjy3i 8eEwS1pVlR7AXf4WfMIOtiMTNHuRzFckrRrEodeEQj594p7j/JMuzSDjf 9RHo48QaFFkKUn1wdsQuzuwyaz/7eA/XAQk9KKCoqgZccsghXcllvsSGF RO0C8hn05oUoz3xohvijDUmUdzRHOQS5LHxR4jwYtUCJLH7DM5G7pq1FQ HdUhjp2jYM41pmjQ8pWTscTN2/oE44NmI/pn6f/ng1Ifn9e48Ofnzu0ki w==; X-IronPort-AV: E=McAfee;i="6200,9189,10267"; a="312828359" X-IronPort-AV: E=Sophos;i="5.88,392,1635231600"; d="scan'208";a="312828359" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Feb 2022 16:06:04 -0800 X-IronPort-AV: E=Sophos;i="5.88,392,1635231600"; d="scan'208";a="491398664" Received: from chakanog-mobl.amr.corp.intel.com (HELO [10.212.198.215]) ([10.212.198.215]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Feb 2022 16:06:03 -0800 Message-ID: Date: Wed, 23 Feb 2022 16:05:59 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Content-Language: en-US To: Abhishek Goel , Dave Hansen Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zi Yan , David Hildenbrand , Yang Shi , Huang Ying , Andrew Morton References: <20210721063926.3024591-1-ying.huang@intel.com> <20210721063926.3024591-2-ying.huang@intel.com> From: Dave Hansen Subject: Re: [PATCH -V11 2/9] mm/migrate: update node demotion order on hotplug events In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,RDNS_NONE,SPF_HELO_NONE, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/23/22 15:02, Abhishek Goel wrote: > If needed, I will provide experiment results and traces that were used > to conclude this. It would be great if you can provide some more info. Even just a CPU time profile would be helpful. It would also be great to understand more about what "hotplug on power systems" actually means. Is this a synthetic benchmark, or are actual end-users running into this issue? Are entire nodes of CPUs going offline? Or is this just doing an offline/online of CPU 22 in a 100-CPU NUMA node?