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From: Christoph Lameter <cl@linux.com>
To: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Subject: Re: [PATCH] slub: Don't throw away partial remote slabs if there is
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On Mon, 3 Feb 2014, Nishanth Aravamudan wrote:

> Yes, sorry for my lack of clarity. I meant Joonsoo's latest patch for
> the $SUBJECT issue.

Hmmm... I am not sure that this is a general solution. The fallback to
other nodes can not only occur because a node has no memory as his patch
assumes.

If the target node allocation fails (for whatever reason) then I would
recommend for simplicities sake to change the target node to NUMA_NO_NODE
and just take whatever is in the current cpu slab. A more complex solution
would be to look through partial lists in increasing distance to find a
partially used slab that is reasonable close to the current node. Slab has
logic like that in fallback_alloc(). Slubs get_any_partial() function does
something close to what you want.