From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760957AbXH2W0M (ORCPT ); Wed, 29 Aug 2007 18:26:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757142AbXH2WZ6 (ORCPT ); Wed, 29 Aug 2007 18:25:58 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:55304 "EHLO e3.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758253AbXH2WZ5 (ORCPT ); Wed, 29 Aug 2007 18:25:57 -0400 Subject: Re: [-mm PATCH] Memory controller improve user interface From: Dave Hansen To: Paul Menage Cc: balbir@linux.vnet.ibm.com, Andrew Morton , Linux Kernel Mailing List , Linux MM Mailing List , David Rientjes , Linux Containers In-Reply-To: <6599ad830708291520t2bc9ea20m2bdcd9e042b3a423@mail.gmail.com> References: <20070829111030.9987.8104.sendpatchset@balbir-laptop> <1188413148.28903.113.camel@localhost> <46D5ED5C.9030405@linux.vnet.ibm.com> <1188425894.28903.140.camel@localhost> <6599ad830708291520t2bc9ea20m2bdcd9e042b3a423@mail.gmail.com> Content-Type: text/plain Date: Wed, 29 Aug 2007 15:25:52 -0700 Message-Id: <1188426352.28903.143.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2007-08-29 at 15:20 -0700, Paul Menage wrote: > > I'd argue that having the user's specified limit be truncated to the > page size is less confusing than giving an EINVAL if it's not page > aligned. Do we truncate mmap() values to the nearest page so to not confuse the user? ;) Imagine a careful application setting and accounting for limits on a long-running system. Might its internal accounting get sufficiently misaligned from the kernel's after a while to cause a problem? Truncating values like that would appear reserve significantly less memory than desired over a long period of time. -- Dave