From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752974AbbLJBPj (ORCPT ); Wed, 9 Dec 2015 20:15:39 -0500 Received: from szxga01-in.huawei.com ([58.251.152.64]:50348 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750715AbbLJBPi (ORCPT ); Wed, 9 Dec 2015 20:15:38 -0500 Message-ID: <5668D1FA.4050108@huawei.com> Date: Thu, 10 Dec 2015 09:14:34 +0800 From: Xishi Qiu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: "Luck, Tony" CC: Taku Izumi , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "kamezawa.hiroyu@jp.fujitsu.com" , "mel@csn.ul.ie" , "Hansen, Dave" , "matt@codeblueprint.co.uk" Subject: Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option References: <1449631109-14756-1-git-send-email-izumi.taku@jp.fujitsu.com> <1449631177-14863-1-git-send-email-izumi.taku@jp.fujitsu.com> <56679FDC.1080800@huawei.com> <3908561D78D1C84285E8C5FCA982C28F39F7F4CD@ORSMSX114.amr.corp.intel.com> In-Reply-To: <3908561D78D1C84285E8C5FCA982C28F39F7F4CD@ORSMSX114.amr.corp.intel.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.25.179] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020206.5668D20E.0042,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: eec7510267af2d5949852f9111a1507e Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/12/10 5:59, Luck, Tony wrote: >> How about add some comment, if mirrored memroy is too small, then the >> normal zone is small, so it may be oom. >> The mirrored memory is at least 1/64 of whole memory, because struct >> pages usually take 64 bytes per page. > > 1/64th is the absolute lower bound (for the page structures as you say). I > expect people will need to configure 10% or more to run any real workloads. > > I made the memblock boot time allocator fall back to non-mirrored memory > if mirrored memory ran out. What happens in the run time allocator if the > non-movable zones run out of pages? Will we allocate kernel pages from movable > memory? > As I know, the kernel pages will not allocated from movable zone. Thanks, Xishi Qiu > -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/ > > . >