[Beowulf] Haswell as supercomputer microprocessors

[Jason Riedy]

And Chris Samuel writes:
> IIRC (not at work to check) HPL is actually part of the BGQ diagnostics; BGQ 
> also has some very useful cable diagnostics that it monitors and flags broken 
> wires up proactively (and has spares to work around them).

And part of most acceptance tests, but those aren't the results
reported on the list.  The variance in commercial systems'
results could be a useful reliability-like metric.