Bill Rea wrote:
> Is this about right for this type of system?
>
> Details:-
>
> Ultra-5 270Mhz CPU, 128Mb RAM
> Solaris 7
> gcc version 2.8.1
For a comparison, I've got some Ultra2s with 2x 200MHz CPUs under Solaris 2.5.1.
One is double-checking some numbers in the 4.6M range (with a 256k FFT)
and is getting approx 0.4s per iteration, and another is checking a number in
the 2.4M range (128k FFT) and is getting 0.22s per iteration. MacLucasUNIX
was compiled with egcs 1.1.2 with
-mcpu=ultrasparc -O6 -funroll-loops -funroll-all-loops
for options.
For 7902277 I'd guess an FFT size of 512k, so you should be getting
roughly double the iteration time divided by 270/200 for CPU speeed -
roughly 0.6s per iteration at a guess. What compiler options were you
using for gcc? I can send you my ultrasparc binary if you want to test
that.
0.4 * 2 * (270/200)
> Also, I've tested MacLucasUNIX with the Sun CC compiler using the
> -fast option and it's about a third faster than when compiled with gcc,
> but there are warnings like:-
>
> The -fast option is unsuitable for programs that require strict
> conformance to the IEEE 754 Standard.
>
> Should I be using this option?
Good question - sounds scary. Unless you get some informed opinion, I'd
be staying clear of that...
Simon.
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