From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754957AbaEVMFM (ORCPT ); Thu, 22 May 2014 08:05:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:5661 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754817AbaEVMFK (ORCPT ); Thu, 22 May 2014 08:05:10 -0400 Message-ID: <1400760284.3145.15.camel@holly> Subject: [PATCH] Documentation: incorrect formula to calculate CommitLimit value From: Petr Oros Reply-To: poros@redhat.com To: rdunlap@infradead.org Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, trivial@kernel.org Date: Thu, 22 May 2014 14:04:44 +0200 Organization: Red Hat Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The formula to calculate "CommitLimit" value mentioned in kernel documentation is incorrect. Right formula is: CommitLimit = ([total RAM pages] - [total huge TLB pages]) * overcommit_ratio / 100 + [total swap pages] Signed-off-by: Petr Oros --- Documentation/filesystems/proc.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 8b9cd8e..b58d764 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -854,7 +854,8 @@ WritebackTmp: Memory used by FUSE for temporary writeback buffers if strict overcommit accounting is enabled (mode 2 in 'vm.overcommit_memory'). The CommitLimit is calculated with the following formula: - CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap + CommitLimit = ([total RAM pages] - [total huge TLB pages]) * + overcommit_ratio / 100 + [total swap pages] For example, on a system with 1G of physical RAM and 7G of swap with a `vm.overcommit_ratio` of 30 it would yield a CommitLimit of 7.3G. -- 1.9.0