Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755868AbbHYOG5 (ORCPT ); Tue, 25 Aug 2015 10:06:57 -0400 Received: from m12-18.163.com ([220.181.12.18]:42861 "EHLO m12-18.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755849AbbHYOGy (ORCPT ); Tue, 25 Aug 2015 10:06:54 -0400 From: Yaowei Bai 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 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> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1440511291-3990-1-git-send-email-bywxiaobai@163.com> References: <1440511291-3990-1-git-send-email-bywxiaobai@163.com> X-CM-TRANSID: EsCowECJ3V21ddxVv1BiAg--.23177S4 X-Coremail-Antispam: 1Uf129KBjvJXoWruFykXrWfWrWrZrWkuFy8Krg_yoW8Jry3p3 ZxK34I9w4rJFyUJrZ3Jw17uFy8Aanayay8Gw1DW395tw1DZF92yFWftrWrX34fGrWIyFWS vFZYqr1rA3WfZFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jSg4fUUUUU= X-Originating-IP: [114.216.26.218] X-CM-SenderInfo: xe1z5x5dretxi6rwjhhfrp/1tbiKxxhT1QG8woEGwAAst Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1481 Lines: 39 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 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/