Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933975AbbFJUmd (ORCPT ); Wed, 10 Jun 2015 16:42:33 -0400 Received: from mga01.intel.com ([192.55.52.88]:27318 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965217AbbFJUkK convert rfc822-to-8bit (ORCPT ); Wed, 10 Jun 2015 16:40:10 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,589,1427785200"; d="scan'208";a="744523393" From: "Luck, Tony" To: Kamezawa Hiroyuki , Xishi Qiu CC: Andrew Morton , "nao.horiguchi@gmail.com" , Yinghai Lu , "H. Peter Anvin" , Thomas Gleixner , "mingo@elte.hu" , Xiexiuqi , Hanjun Guo , Linux MM , LKML Subject: RE: [RFC PATCH 10/12] mm: add the buddy system interface Thread-Topic: [RFC PATCH 10/12] mm: add the buddy system interface Thread-Index: AQHQnscWKDg7SoiYFUq3OAjydtKYB52kPxgAgAAwCYCAAR1/gIAArv9A Date: Wed, 10 Jun 2015 20:40:08 +0000 Message-ID: <3908561D78D1C84285E8C5FCA982C28F32A8F209@ORSMSX114.amr.corp.intel.com> References: <55704A7E.5030507@huawei.com> <55704CC4.8040707@huawei.com> <557691E0.5020203@jp.fujitsu.com> <5576BA2B.6060907@huawei.com> <5577A9A9.7010108@jp.fujitsu.com> In-Reply-To: <5577A9A9.7010108@jp.fujitsu.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.22.254.139] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 923 Lines: 18 > I guess, mirrored memory should be allocated if !__GFP_HIGHMEM or !__GFP_MOVABLE HIGHMEM shouldn't matter - partial memory mirror only makes any sense on X86_64 systems ... 32-bit kernels don't even boot on systems with 64GB, and the minimum rational configuration for a machine that supports mirror is 128GB (4 cpu sockets * 2 memory controller per socket * 4 channels per controller * 4GB DIMM ... leaving any channels empty likely leaves you short of memory bandwidth for these high core count processors). MOVABLE is mostly the opposite of MIRROR - we never want to fill a kernel allocation from a MOVABLE page. I want all kernel allocations to be from MIRROR. -Tony -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/