Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request From: steinmetz!grymoire!barnett@uunet.uu.net (Bruce Barnett) Newsgroups: comp.sys.sun Subject: Re: SUN-4 FPU Message-ID: <8902211401.AA02161@grymoire.steinmetz.Ge.Com> Date: 3 Mar 89 22:02:14 GMT Sender: usenet@rice.edu Organization: Sun-Spots Lines: 32 Approved: Sun-Spots@rice.edu Original-Date: Tue, 21 Feb 89 09:01:13 EST X-Sun-Spots-Digest: Volume 7, Issue 179, message 4 of 11 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 uunet!steinmetz!barnett