Sun 3 vs uVAXII floating point speed....

[Ehud Reiter]

In article <25065 at ucbvax.BERKELEY.EDU> ao at cevax.berkeley.edu (Akin Ozselcuk) writes:
>Sun 3 seems very impressive in this respect BUT CAN WE SAY THAT
>Sun 3 IS 3 TIMES FASTER IN FLOATING POINT CALCULATIONS THAN uVAX

The following data is from J. Dongarra, "Performance of Various Computers
Using Standard Linear Equation Software in a Fortran Environment", COMPUTER
ARCHITECTURE NEWS, vol16, no 1 (March 1988):

(from Table 1 - full (i.e. double) precision, no assembly subroutines)
Machine			Mflops
Sun 4/260		1.1
Sun 3/260 with FPA	 .46
uVAX 3200 (VMS)		 .41
Sun 3/160 with FPA	 .40
uVAX II (VMS)		 .13
Sun 3/260 with 68881	 .11
Sun 3/160 with 68881	 .10
Sun 3/50 with 68881	 .087
uVAX II (Ultrix)	 .082

(and, just for fun)
CRAY X-MP-4	      480	(with vector unrolling, assembly subroutines)
Alliant FX/8	       27	(with vector unrolling, assembly subroutines)
uVAX II (VMS)		 .16	(with assembly subroutines)
IBM PC/AT with 80287	 .012	(using PROFORT 1.0 compiler)


Readers can draw their own interpretations.  Note that while I think
Dongarra's LINPACK is one of the most honest benchmarks around (and far
better than, say, Dhrystone), it, like all benchmarks, still needs to
be taken with a very large grain of salt.

					Ehud Reiter
					reiter at harvard	(ARPA,BITNET,UUCP)
					reiter at harvard.harvard.EDU  (new ARPA)