R6515 with unbalanced memory config?

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All-

We ordered a small number of R6515 servers with AMD EPYC 7302P processors
with only 2 DIMM slots populated and I'm trying to figure out how much of
a problem this is going to be.  These will be running either RHEL 7.x
(3.10 kernel + RHEL backports / "vendor sauce") or RHEL 8 (4.18.0 kernel
+ RHEL backports).  Anyone have any experience with what the NUMA
unbalanced memory penalty may be in this situation?

We were under a tight deadline when we ordered these systems, and I hadn't
at the time seen any of the memory config recommendations.  That's on me.

Dell's system config portal never even hinted that populating just
2 DIMM slots might be a problem, though.

I've since found this blog post:

 	https://blog.dellemc.com/en-us/2nd-generation-amd-epyc-processors-poweredge-servers/

(which looks to be copied verbatim without attribution here:
https://jtekds.com/balanced-memory-is-best-2nd-generation-amd-epyc-processors-for-poweredge-servers/)

But the full whitepaper is no longer present on Dell's download site.
Even finding the 1 page

 	http://downloads.dell.com/manuals/common/Direct_from_Development_-_Balanced_Memory_on_2nd_Generation_AMD_EPYC_Processors_Reference_Guide.pdf

Still links to the full whitepaper under a download URL that no longer
works.

Anyone know either where the full whitepaper can be found or what kind of
performance penalty we're looking at for this type of NUMA memory config?

Thanks,

Tim
-- 
Tim Mooney                                             [email protected]
Enterprise Computing & Infrastructure /
Division of Information Technology    /                701-231-1076 (Voice)
North Dakota State University, Fargo, ND 58105-5164