Sun 4/110 without FPA is slower than a 3/50 without MC68881
Bruce Barnett
barnett at steinmetz.ge.com
Thu Jan 26 16:30:53 AEST 1989
I just did a benchmark on a Sun 4/110 without the FPA option.
The benchmark is:
__________
main() {
int i = 100000;
double f = 0.0;
while (i--) f += 1.0;
printf("f=%g\n",f);
}
__________
Compiled on a 4.0.1 system using cc -O4
Results: (using csh's time command:)
Sun 4/280 0.2u 0.1s 0:00 70% 0+128k 0+0io 0pf+0w
Sun 3/50 -f68881 0.4u 0.1s 0:00 106% 0+72k 0+0io 0pf+0w
Sun 3/50 -fsoft 5.7u 0.2s 0:06 96% 0+72k 0+0io 1pf+0w
Sun 4/110 - No FPA 0.8u 45.0s 0:46 99% 0+136k 0+0io 0pf+0w
I assume this is due to:
Compiler always assumes the FPA chip is *ALWAYS* there.
FP calls are trapped by the kernal and the hardware is emulated
I also assume that Sun Marketing made a promise to engineering that Sun
4's will always have the FPA chip. And of course the engineers believed
them.
I also assume that they were soooooo embarrassed, that Marketing tried to
cover up the fact that a Sun 4/110 is *90 times slower* than a Sun 3/50
w/68881.
******FLAME ON TO SUN*******
You can't hide this sort of information, you twits. I knew the machine
would be slow for floating point, but if I knew it would make a PC look
like a Cray in comparison, I would not have ordered this configuration.
Sheeesh!
--
Bruce G. Barnett barnett at ge-crd.ARPA, barnett at steinmetz.ge.com
uunet!steinmetz!barnett
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