On Wed, 23 Feb 2000 23:32:25 -0800, Anton Sherwood <bro### [at] poboxcom>
wrote:

>I recently replaced my Mac clone (PPC, 180 MHz) with a Linux box (K7,
>550 MHz).  I installed povray and found it surprisingly fast.  How
>fast?  I tried a scene that I remembered as taking three hours, and it
>was done in 8m 21s.
>
>With a 3x difference in nominal CPU speed, why this 20x difference in
>rendering?
>Does the Mac compiler fail to use the math chip efficiently?  Is the
>math chip just crap?

The Athlon has a faster RAM bus, much more internal clock-speed cache,
three fully separate conveyours for RISC instructions and what-not.
Also, there's the (slight) overhead of a GUI that you're usually not
bound to see in Linux. Also, the Linux kernel 2.2.13 (maybe some
earlier do, too) makes good use of memory type range registers, and
the athlon has three (or four?) of those. Also, the Linux compile is a
truly native one (i.e. for your machine) and the Mac compile was
optimized for a more general audience.

MACs are good machines, true RISC and all. Maybe you should try
testing again in a more "laboratoty" environment?


Peter Popov
pet### [at] usanet
ICQ: 15002700

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