Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!usc!elroy.jpl.nasa.gov!thyme!kaleb
From: kaleb@thyme.jpl.nasa.gov (Kaleb Keithley	)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Re: 386 vs 386SX
Message-ID: <1990Dec11.163854.19706@thyme.jpl.nasa.gov>
Date: 11 Dec 90 16:38:54 GMT
References: <1990Dec10.024523.21545@xrtll.uucp> <1990Dec10.161538.16651@thyme.jpl.nasa.gov> <17755@neptune.inf.ethz.ch>
Distribution: comp.sys.ibm.pc.misc
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 38

In article <17755@neptune.inf.ethz.ch> brandis@inf.ethz.ch (Marc Brandis) writes:
>I wrote:
>>
>>For what it's worth, I get the following Dhrystone's:
>>(Yeah, I know Dhrystone isn't the do all benchmark; anyone got the
>>source to Bytes' PC benchmarks?)
>>
>>16mhz 386SX       20mhz 386DX       25mhz 486       Sun 4/330
>>5000              8000              28000           24000
>>
>
>Without any further information these benchmarks do not really tell you
>anything about the relative performance of an SX to a DX or even a 486 or a
>Sun 4. What kind of memory system do the used systems have, are they cached

Thank you.  Why don't you re-read what I said ("For what it's worth, ....") 
which means you can put whatever value on it that you want; probably none.

All three INTeL machines used 80ns DRAM, the 486 has 128k of 35ns SRAM cache.
The INTeL machines under MS-DOS using M'soft C 5.1. and under ESIX SVR3.2
using gcc.  The Sun running SunOS 4.x.  INTeL machines on ISA bus.  Sun
is (of course) VME bus.  No, the results between SVR3 and MS-DOS weren't
exactly the same, but were not materially different.  In general, SVR3
results were slightly slower than the DOS results.

I also prefaced my post with a disclaimer about Dhrystone.  My post was
in reponse to a debate about whether an SX could be as fast as a DX under
any circumstances.  I thought (silly me) that some raw numbers might help
resolve the debate.  There is a lot more to how fast the machine is than
just some memory-only processing.  A slow disk drive, or a slow bus arche-
tecture, or slow video I/O can bring a screamer to a screaching halt.
But then I did ask for the source to the Byte benchmarks, didn't I.

-- 
Kaleb Keithley                      Jet Propulsion Labs
kaleb@thyme.jpl.nasa.gov

You can please all of the people some of the time,