VIA C3

[Damian Gerow]

(Talking about CPUTYPE for Via C3 chips, and whether i586/mmx or k6-3 is
better.)

Thus spake Damian Gerow (damian at sentex.net) [18/06/03 11:31]:
> > Back to the performance-discussion between cputype 586/mmx and k6-3
> > optimization: do you have a suggestion how to benchmark it?
> 
> Well, there's always /usr/ports/benchmarks.  nbench might be what you're
> looking for -- compile it once using 586/mmx support, and once using k6-3
> support.

FWIW, I ran some quick nbench tests on my system.  World and kernel compiled
with i586/mmx.

Here's the results from compiling with k6-3:

    TEST                : Iterations/sec.  : Old Index   : New Index
                        :                  : Pentium 90* : AMD K6/233*
    --------------------:------------------:-------------:------------
    NUMERIC SORT        :          213.91  :       5.49  :       1.80
    STRING SORT         :          17.112  :       7.65  :       1.18
    BITFIELD            :       4.347e+07  :       7.46  :       1.56
    FP EMULATION        :          14.949  :       7.17  :       1.66
    FOURIER             :          2315.8  :       2.63  :       1.48
    ASSIGNMENT          :          3.8335  :      14.59  :       3.78
    IDEA                :          362.06  :       5.54  :       1.64
    HUFFMAN             :          226.37  :       6.28  :       2.00
    NEURAL NET          :          3.1664  :       5.09  :       2.14
    LU DECOMPOSITION    :          164.11  :       8.50  :       6.14

And with i586/mmx:

    TEST                : Iterations/sec.  : Old Index   : New Index
                        :                  : Pentium 90* : AMD K6/233*
    --------------------:------------------:-------------:------------
    NUMERIC SORT        :          220.27  :       5.65  :       1.86
    STRING SORT         :          16.913  :       7.56  :       1.17
    BITFIELD            :      4.3313e+07  :       7.43  :       1.55
    FP EMULATION        :          15.028  :       7.21  :       1.66
    FOURIER             :          2310.2  :       2.63  :       1.48
    ASSIGNMENT          :          3.3773  :      12.85  :       3.33
    IDEA                :          367.09  :       5.61  :       1.67
    HUFFMAN             :          212.37  :       5.89  :       1.88
    NEURAL NET          :          3.0659  :       4.93  :       2.07
    LU DECOMPOSITION    :          155.45  :       8.05  :       5.82

So it looks like it's a tossup between the two, with k6-3 perhaps pulling
out marginally ahead.

Multiple runs of the tests with each flags show numbers extremely close to
the ones posted, if not exactly the same.