reliable/reproduceable benchmarks on SGI MIPS box

[Phil Dench]

andrew at alice.att.com (Andrew Hume) writes:


>	I am running some benchmarks on a variety of machines
>and in particular, on a SGI 4D/380, a multiprocesor with 8
>33MHz R3000 cpus. my benchmark reads in about 1.1MB of text
>into an internal buffer and then runs cpu bound for about
>40s. total memory usage is <2MB; the machine's memory is 256MB.
>The benchmarks are run with the machine in single user (Unix)
>mode with normally mounted NFS filesystems unmounted. No other
>processes (excpet paging daemon etc) are running.

>	my problem is that I see quite large variations over
>multiple runs of the same benchmark, sometimes as much as
>1.26%. Now, the resolution of the timer is .01s and i should se
>an accuracy of about .01/40 or .025%. I am a factor of 50 off this.
>does anyone know how i can run these benchmarks so as to get reproducible
>timings? (i note as an aside that just running the benchmarks on the cray
>in multi-user mode yields variations of the order of .15% which is
>satisfactory).

>	andrew hume
>	andrew at research.att.com

You LUCKY BASTARD! I dream of 256Mb 8 processor SG plus access to a Cray.
There's no pleasing some people :?)
--

	Phil Dench  Andrew Marriott.

--------------------------------------------+----------------------------------
                                            | School of Computer Science,
ACSNet: raytrace at cutmcvax.cs.curtin.edu.au  | Curtin University of Technology,
UUCP:   ...!uunet!munnari!cutmcvax!raytrace | Kent Street,
ARPA:   raytrace at cutmcvax.cs.curtin.edu.au  | Bentley
                                            | Western Australia, 6102
--------------------------------------------+----------------------------------