From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f176.google.com (mail-yk0-f176.google.com [209.85.160.176]) by kanga.kvack.org (Postfix) with ESMTP id CA8989003C7 for ; Tue, 25 Aug 2015 10:04:43 -0400 (EDT) Received: by ykfw73 with SMTP id w73so157058034ykf.3 for ; Tue, 25 Aug 2015 07:04:43 -0700 (PDT) Received: from m12-18.163.com (m12-18.163.com. [220.181.12.18]) by mx.google.com with ESMTP id p9si12468675ywc.99.2015.08.25.07.04.41 for ; Tue, 25 Aug 2015 07:04:43 -0700 (PDT) From: Yaowei Bai Subject: [PATCH 2/2] Documentation: clarify in calculating zone protection Date: Tue, 25 Aug 2015 22:01:31 +0800 Message-Id: <1440511291-3990-2-git-send-email-bywxiaobai@163.com> In-Reply-To: <1440511291-3990-1-git-send-email-bywxiaobai@163.com> References: <1440511291-3990-1-git-send-email-bywxiaobai@163.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, mgorman@suse.de, vbabka@suse.cz, mhocko@kernel.org, js1304@gmail.com, hannes@cmpxchg.org, alexander.h.duyck@redhat.com, sasha.levin@oracle.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Every zone's protection is calculated from managed_pages not present_pages, to avoid misleading, correct it. 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org