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[2620:137:e000::1:20]) by mx.google.com with ESMTP id z11-20020a056870460b00b000dd9a4d8102si13927158oao.158.2022.03.29.09.08.23; Tue, 29 Mar 2022 09:08:37 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=K4f+qPgg; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232959AbiC2Ocz (ORCPT + 99 others); Tue, 29 Mar 2022 10:32:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230270AbiC2Ocy (ORCPT ); Tue, 29 Mar 2022 10:32:54 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E4FF1BE8E for ; Tue, 29 Mar 2022 07:31:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648564272; x=1680100272; h=message-id:date:mime-version:to:cc:references:from: subject:in-reply-to:content-transfer-encoding; bh=MPEyK90txtRaPxxSHUlpyihpzVwxdEsPaW015RjFxuo=; b=K4f+qPggOtp8N2NWE2GHXQcGTkbPahUCCKT1SJUJT0sF10cnHACfZEcV 0/9ydzj61sUZ/Rad8mH/YO6LDQCwzJuHbndQ6iBtQZAw5GsngMPxNMMio SkLLmKYz4F9YRa9sEkLSEVjx2GMNFvt7ckxDqeHk1MgUdoaxqyp8ZWe7I hlf1kVtm4VTWnJdcUlud+mKQzFVHkfNn/W6Pz3Yf83+bfLGAWosdrZEYx 4SnLiP2vz0UH98Wm2HUORhBw47eDTFM3LWi8YirffbYPM05GZlI/zLyyC AokvjX55Zqrh50W54kzEOPWcZr/eLLg6i5CIpqmaqdSmOM2tCKqJ6WFFH Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10301"; a="322447300" X-IronPort-AV: E=Sophos;i="5.90,220,1643702400"; d="scan'208";a="322447300" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2022 07:31:11 -0700 X-IronPort-AV: E=Sophos;i="5.90,220,1643702400"; d="scan'208";a="604810742" Received: from acstuden-mobl.amr.corp.intel.com (HELO [10.209.45.17]) ([10.209.45.17]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2022 07:31:11 -0700 Message-ID: <55161160-1084-c81d-d116-00f5bcaa1268@intel.com> Date: Tue, 29 Mar 2022 07:31:12 -0700 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: Jagdish Gediya , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, baolin.wang@linux.alibaba.com, dave.hansen@linux.intel.com, ying.huang@intel.com References: <20220329115222.8923-1-jvgediya@linux.ibm.com> From: Dave Hansen Subject: Re: [PATCH] mm: migrate: set demotion targets differently In-Reply-To: <20220329115222.8923-1-jvgediya@linux.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A, RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham 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 3/29/22 04:52, Jagdish Gediya wrote: > The current implementation to identify the demotion > targets limits some of the opportunities to share > the demotion targets between multiple source nodes. This changelog is a bit unsatisfying. It basically says: the current code isn't working, throw some more code at the problem. I'd love to see some more information about *why* the current code doesn't work. Is it purely a bug or was it mis-designed? I actually wrote it intending for it to handle cases like you describe while not leaving lots of nodes without demotion targets.