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SubjectRe: [patch 6/6] mempolicy: update NUMA memory policy documentation
+	MPOL_F_RELATIVE_NODES:  This flag specifies that the nodemask passed
+ by the user should remain in the same context as it is for the
+ current task or VMA's set of accessible nodes after the memory
+ policy has been defined.
+
+ Without this flag (and without MPOL_F_STATIC_NODES), anytime a
+ mempolicy is rebound because of a change in the set of
+ accessible nodes, the node (Preferred) or nodemask (Bind,
+ Interleave) is remapped to the new set of accessible nodes.
+ With this flag, the remap is done to ensure the context of the
+ previous nodemask with its set of allowed mems is preserved.

Hmmm ... I've read this several times now ... still can't figure out
what it's saying ;). And it doesn't really explain key aspects of
MPOL_F_RELATIVE_NODES, such as that it provides cpuset relative
numbering (use nodes 0..N-1, regardless of your current cpuset, to
refer to the first N nodes in whatever is your current cpuset.)

Perhaps we'd be further ahead of the game if you started with the
documentation changes to Documentation/vm/numa_memory_policy.txt,
in my patch:
Date: Sun, 23 Dec 2007 22:24:02 -0600
From: Paul Jackson <pj@sgi.com>
To: David Rientjes <rientjes@google.com>
Cc: Lee.Schermerhorn@hp.com, clameter@sgi.com
Subject: Re: [RFC] cpuset relative memory policies - second choice
Message-Id: <20071223222402.5486bf0a.pj@sgi.com>

Change MPOL_MASK_REL to MPOL_F_RELATIVE_NODES and similar changes.

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.940.382.4214


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