Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755848AbbHYPGh (ORCPT ); Tue, 25 Aug 2015 11:06:37 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:35387 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751813AbbHYPGg (ORCPT ); Tue, 25 Aug 2015 11:06:36 -0400 Date: Tue, 25 Aug 2015 17:06:33 +0200 From: Michal Hocko To: Yaowei Bai Cc: akpm@linux-foundation.org, mgorman@suse.de, vbabka@suse.cz, js1304@gmail.com, hannes@cmpxchg.org, alexander.h.duyck@redhat.com, sasha.levin@oracle.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] Documentation: clarify in calculating zone protection Message-ID: <20150825150633.GG6285@dhcp22.suse.cz> References: <1440511291-3990-1-git-send-email-bywxiaobai@163.com> <1440511291-3990-2-git-send-email-bywxiaobai@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1440511291-3990-2-git-send-email-bywxiaobai@163.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1974 Lines: 53 On Tue 25-08-15 22:01:31, Yaowei Bai wrote: > Every zone's protection is calculated from managed_pages not > present_pages, to avoid misleading, correct it. This can be folded in to your previous patch http://marc.info/?l=linux-mm&m=144023106610358&w=2 > > Signed-off-by: Yaowei Bai > --- > Documentation/sysctl/vm.txt | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt > index 9832ec5..1739b31 100644 > --- a/Documentation/sysctl/vm.txt > +++ b/Documentation/sysctl/vm.txt > @@ -349,7 +349,7 @@ zone[i]'s protection[j] is calculated by following expression. > > (i < j): > zone[i]->protection[j] > - = (total sums of present_pages from zone[i+1] to zone[j] on the node) > + = (total sums of managed_pages from zone[i+1] to zone[j] on the node) > / lowmem_reserve_ratio[i]; > (i = j): > (should not be protected. = 0; > @@ -360,7 +360,7 @@ The default values of lowmem_reserve_ratio[i] are > 256 (if zone[i] means DMA or DMA32 zone) > 32 (others). > As above expression, they are reciprocal number of ratio. > -256 means 1/256. # of protection pages becomes about "0.39%" of total present > +256 means 1/256. # of protection pages becomes about "0.39%" of total managed > pages of higher zones on the node. > > If you would like to protect more pages, smaller values are effective. > -- > 1.9.1 > > > -- > 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/ -- Michal Hocko SUSE Labs -- 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/