[Numpy-discussion] Adding a 2D with a 1D array...

Francesc Alted faltet at pytables.org
Thu Sep 10 08:32:34 EDT 2009


A Thursday 10 September 2009 14:22:57 Dag Sverre Seljebotn escrigué:
> >  > (Also a guard in timeit against CPU frequency scaling errors would be
> >  >
> >  > great :-) Like simply outputting a warning if frequency scaling is
> >  >
> >  > detected).
> >
> > Sorry, I don't get this one.
>
> I had some trouble getting reliable benchmarks on my own computer until
> I realised that the power-saving capabilities of my CPU down-throttled
> the clock speed when it was not in use. Thus if I did two calls to
> timeit right after one another, the second would always report lower
> runtime, because the first one started at a lower clock speed.

:-)  Good point

>
> Changing a BIOS setting solved this, but it might be a gotcha which e.g.
> timeit and IPython could report (they could just inspect the CPU
> information and emit a warning -- or, do something to throttle up the
> CPU to full speed first).

-- 
Francesc Alted
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