From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762014AbYCAA6G (ORCPT ); Fri, 29 Feb 2008 19:58:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752297AbYCAA5y (ORCPT ); Fri, 29 Feb 2008 19:57:54 -0500 Received: from rgminet01.oracle.com ([148.87.113.118]:13489 "EHLO rgminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750921AbYCAA5x (ORCPT ); Fri, 29 Feb 2008 19:57:53 -0500 Message-ID: <47C8A982.4080302@oracle.com> Date: Fri, 29 Feb 2008 16:55:30 -0800 From: Randy Dunlap User-Agent: Thunderbird 1.5.0.5 (X11/20060719) MIME-Version: 1.0 To: David Rientjes CC: Andrew Morton , Paul Jackson , Christoph Lameter , Lee Schermerhorn , Andi Kleen , linux-kernel@vger.kernel.org Subject: Re: [patch 6/6] mempolicy: update NUMA memory policy documentation References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org David Rientjes wrote: > Updates Documentation/vm/numa_memory_policy.txt and > Documentation/filesystems/tmpfs.txt to describe optional mempolicy mode > flags. > > Cc: Christoph Lameter > Cc: Lee Schermerhorn > Cc: Andi Kleen > Cc: Randy Dunlap > Signed-off-by: David Rientjes > Signed-off-by: Paul Jackson > --- > Documentation/filesystems/tmpfs.txt | 12 +++ > Documentation/vm/numa_memory_policy.txt | 131 +++++++++++++++++++++++------- > 2 files changed, 112 insertions(+), 31 deletions(-) > > diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.txt > --- a/Documentation/vm/numa_memory_policy.txt > +++ b/Documentation/vm/numa_memory_policy.txt > @@ -231,6 +234,80 @@ Components of Memory Policies > the temporary interleaved system default policy works in this > mode. > > + Linux memory policy supports the following optional mode flag: flags: > + > + MPOL_F_STATIC_NODES: This flag specifies that the nodemask passed by > + the user should not be remapped if the task or VMA's set of allowed > + nodes changes after the memory policy has been defined. > + > + Without this flag, anytime a mempolicy is rebound because of a > + change in the set of allowed nodes, the node (Preferred) or > + nodemask (Bind, Interleave) is remapped to the new set of > + allowed nodes. This may result in nodes being used that were > + previously undesired. > + > + With this flag, if the user specified nodes overlap with the user-specified > + nodes allowed by the task's cpuset, then the memory policy is > + applied to their intersection. If the two sets of nodes do not > + overlap, the Default policy is used. > + > + For example, consider a task that is attached to a cpuset with > + mems 1-3 that sets an Interleave policy over the same set. If > + the cpuset's mems change to 3-5, the Interleave will now occur > + over nodes 3, 4, and 5. With this flag, however, since only node > + 3 is allowed from the user's nodemask, the "interleave" only > + occurs over that node. If no nodes from the user's nodemask are > + now allowed, the Default behavior is used. > + > + MPOL_F_STATIC_NODES cannot be used with MPOL_F_RELATIVE_NODES. > + -- ~Randy