Re: [PATCH -V6 RESEND 1/3] numa balancing: Migrate on fault among multiple bound nodes

"Huang, Ying" [off-list ref] writes:

Peter Zijlstra [off-list ref] writes:

quoted

On Wed, Dec 02, 2020 at 11:40:54AM +0000, Mel Gorman wrote:

quoted

On Wed, Dec 02, 2020 at 04:42:32PM +0800, Huang Ying wrote:

quoted

Now, NUMA balancing can only optimize the page placement among the
NUMA nodes if the default memory policy is used.  Because the memory
policy specified explicitly should take precedence.  But this seems
too strict in some situations.  For example, on a system with 4 NUMA
nodes, if the memory of an application is bound to the node 0 and 1,
NUMA balancing can potentially migrate the pages between the node 0
and 1 to reduce cross-node accessing without breaking the explicit
memory binding policy.

Ok, I think this part is ok and while the test case is somewhat
superficial, it at least demonstrated that the NUMA balancing overhead
did not offset any potential benefit

Acked-by: Mel Gorman <mgorman@suse.de>

Who do we expect to merge this, me through tip/sched/core or akpm ?

Hi, Peter,

Per my understanding, this is NUMA balancing related, so could go
through your tree.

BTW: I have just sent -V7 with some small changes per Mel's latest
comments.

Hi, Andrew,

Do you agree?

So, what's the conclusion here?  Both path works for me.  I will update
2/3 per Alejandro Colomar's comments.  But that's for man-pages only,
not for kernel.  So, we can merge this one into kernel if you think it's
appropriate.

Best Regards,
Huang, Ying