Hello Ian,

> I have never been able to get anything like realistic FLOPS numbers
> from PAPI. I have not tried recently.  I think I heard that the
> hardware counter interfaces were only ever originally intended as
> debugging tools to be used by the processor manufacturers themselves,
> and were quite unreliable.  This might have changed in recent CPUs.
> Do you get numbers consistent with what you expect?  BlueWaters
> doesn't use very recent CPUs.  I didn't know that the PAPI thorn
> tests this; that is nice!
BW is likely one of the better candidates for good numbers since PAPI
is supported by Cray (https://bluewaters.ncsa.illinois.edu/papi). There
are even (non user accessible) counters that always count how many
flops are used in a job and that one can query (unless the user code
uses PAPI in which case the counters are not usable by the system). 

PAPI (or at least the counters) is pretty much my only hope as counting
the number of flops in a GR+Hydro+AMR+Neutrino simulation is quite


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