Re: Performance question

["Justin C. Walker" <justin@mac.com>]

On Thursday, July 10, 2003, at 07:34 AM, Bill Allombert wrote:

> On Wed, Jul 09, 2003 at 02:31:56PM -0700, justin@mac.com wrote:
> > Hi, all,
> >
> > There may be something obvious that I'm overlooking, but I am seeing a
> > performance difference between two machines that seems
> > counter-intuitive.
> >
> > I have gp on two Mac OS X systems (10.2.6 and, um, another one).
> > 10.2.6 is on a 450Mhz G4, while the other one is on a 300Mhz G3.  When
> > I ran 'make bench' on the G3, it seemed to do much better than on the
> > G4.
>
> > parisize = 4000000, primelimit = 500000
> > ============================================================
> >
> > FWIW, gcc on the G4 is 3.1, and on the G3 is 3.3.
>
> Care to try with the same compiler on both machines ?

I will give it a try; it's not entirely straightforward, though.

> Most probably the difference come from the compiler. The other
> possibility is the assembly kernel that can be faster on one CPU than 
> on
> the other but I doubt it.

Given the performance differences between G3 and G4 (G3 < G4), both 
explanations seem problematic, but I don't have enough experience with 
gcc 3.3 to be sure.

I will fiddle around some more and see what I can find.

Thanks!

Regards,

Justin

--
Justin C. Walker, Curmudgeon-At-Large  *
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