DUAL CPU board vs 2 Single CPU boards: bang for buck?

[Josip Loncaric]

"Robert G. Brown" wrote:
> 
>   Your Mileage May Vary

Exactly.  The cost of duals is about 15% lower per CPU, but some codes
(e.g. CFD) perform about 25% worse on duals due to memory contention. 
If you do CFD, price/performance can favor singles by about 10%; if you
do something less memory intensive, duals win by about 15%.  Other
factors (such as space efficiency, power/AC requirements,
simplicity/reliability, personal preferences) are often more significant
than these 10-15% differences in node price/performance.

One exception: If you use a high end network (e.g. Myrinet, which can
almost double the cost of a node) this clearly favors duals which need
only half as many expensive network connections.

Sincerely,
Josip

-- 
Dr. Josip Loncaric, Research Fellow               mailto:josip at icase.edu
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