Hello,

> >  An XScale based PocketPC is coming out in a few weeks from
> >Toshiba.  I would assume that XScale at 400MHz (max) is
> >faster than 300MHz Geode:-)
> 
> Well, that depends....  If you mean the PXA210, then I
> would say that the 300 MHz Geode definitely beats the 400
> MHz XScale.  The Geode is essentially a Pentium class CPU
> with floating point and MMX.  I'd say that it is probably
> still faster than even a 400 MHz PXA250, especially for
> running Squeak. 

  Hmm.  Interesting.

> Squeak likes hardware floating point.  Compare Squeak on a
> 200 MHz Celeron against Squeak on an iPaq.  I know for
> sure that Squeak is much more responsive and the
> benchmarks are better on my old Pentium 133 Sharp Widenote
> that on my Casiopeia E-105 (a 131 MHz MIPS 3 CPU with no
> floating point hardware).

  Do you think this is due to the floating point hardware?
I've been thinking this is more because of the memory
bandwidth.

  On my Pentium III 800MHz laptop, the ratio of results from 
following two lines is around 2.4. (43ms vs. 103ms).

[100000 timesRepeat: [0+0]] timeToRun.
[100000 timesRepeat: [0.0+0.0]] timeToRun.

On my iPAQ, the ratio is around 2.3.  I think the primitive
callout is so slow that the actual computation is pretty
much shadowed by the other factor.  The #+ primitive first
trys SmallInteger version and then fall back to Float
version.  This would explain the factor of two difference.

> I don't think Squeak would readily take advantage of the
> dual multiply-accumulate pipelines or SIMD on the PXA250,
> just like it doesn't really benefit from MMX.

  Yes.  Some bitblt rules, such as rule 24 can be much
faster if we bind it with the MMX (or Intel IPP stuff).

-- Yoshiki