SUN-4 FPU

[Bruce Barnett]

Marcel Bernards says:
>So SUN 4/110 _does_ emulate FP .

Maybe there is a communication problem, but Skip and I never said the Sun
4/110 doesn't emulate the FPU.

The problem is that the emulation appears to require a kernal trap.  Look
at the time the program spends in the system mode:

>SUN 4/110 NOCO
>1.2u 31.1s 0:32 99% 0+136k 2+9io 2pf+0w

That's thiry one seconds in the kernel (system) mode.

The results for a 3/50 without FPU is:
	6.0u 0.2s 0:06 94% 0+72k 0+1io 0pf+0w

And the system time is 0.2 seconds. 

Of *course* the Sun 4 is emulating the FPU.

I just wished I could use a library routine, the GNU cc compiler,
ANYTHING, so I wouldn't have to suffer from all those traps. Does anyone
have any ideas not requiring $$?

Does anyone have any ideas on how I can measure the number of traps I get
so I can estimate the penalty I pay? (I use NeWS a lot).

Of course I could always use a 3/50 as a compute server....
--
Bruce G. Barnett  <barnett at ge-crd.ARPA> <barnett at steinmetz.ge.com>
		uunet!steinmetz!barnett