SparcStation Performance

[MORGENSTERN at TCUAVMS.BITNET]

A while back there was some discussion about what a MIP measured, and more
recently there have been some queries about SparcStation performance from
perspective buyers.  I do work on heuristics for combinatiorial
optimization, and have been testing heuristics on a 3/60 (running at 3
MIPS I'm told) with 8 Megs and no floating point coprocessor.  Recently,
we took delivery on a SparcStation I (8 Megs with a floating point
coprocessor) that is rated in excess of 10 MIPS (again -- so I'm told).

The point of this note is that no uniform speedup was observed going from
the 3/60 to the SparcStation.  At one extreme, a C program that does
intensive floating point work ran 36 times FASTER on the SparcStation
(this speedup would be much less if the 3/60 had floating point
coprocessor), and at the other extreme, a C program that uses numerous
data structures implemented using bitwise ops ran 1.7 times SLOWER on the
SparcStation (this program also does some floating point ops, so the
slowdown would be worse if the 3/60 had a floating point coprocessor).

We've also noticed that the SparcStation becomes quite slow when someone
is doing nothing more than editing a file on the console (slow to the
point that vi acts like the load average is up around 10 or so when it is
actually less than one).  This is not observed when several people are
logged on via ethernet -- only when the console is being used.  We have
lots of swap space (32 Megs), a small optimized kernel and the "standard"
327 Meg shoebox.