[comp.sys.ibm.pc] Performance of 386SX

carpio@questor.wimsey.bc.ca (antonio carpio) (06/04/90)

I recently purchased a 386SX computer with an IDE 80 meg Miniscribe drive, a 
a 1:1 interleave factor, 0.3 wait state, 2 meg RAM.  In running some 
diagnostic tests, I got the following results:
  MIPS   1.91
  Coretest - Data Transfer Rate 460 Kb/sec; Ave. seek 18.9; Track-Track Seek 
Seek 6.2; Overall performance 5.654.  Speed 18.8 Mz.
Can someone please tell me:  (1)  Are these good or bad results?  (2)  For
the bad results, what may be the limiting factor?  (3)  Any suggestions on 
how to improve the performance?  Thanks for any help you can offer.

root@kesher.UUCP (Aaron_Schmiedel) (06/04/90)

Your MIPS and Coretest ratings look pretty good.  You may want to
check your buss speed (if you have the Chips & Technology chip set)
and try upping the speed on it a little.  USUALLY (but there are many
factors dependant) the data transfer rate should be around 600K -
but that is under optimum conditions.  At 460K, you are still doing
a GREAT job compared to the standard MFM stuff.
  
BUT, the IDE has on-board disk-caching (usually about 64K worth) so
this shows as a significant speedup in Coretest.  
  
Those numbers are great, but remember the most important factor:
  
Are you happy with the way it is performing?

shwake@raysnec.UUCP (Ray Shwake) (06/05/90)

In article <TXa9J1w162w@questor.wimsey.bc.ca> carpio@questor.wimsey.bc.ca (antonio carpio) writes:
>  MIPS   1.91
>  Coretest - Data Transfer Rate 460 Kb/sec; Ave. seek 18.9; Track-Track Seek 
>Seek 6.2; Overall performance 5.654.  Speed 18.8 Mz.

Your results are typical for the class of machine under question, but I
wouldn't take the Data Transfer Rate too seriously. Since you don't specify
the block size used by Coretest, I assume you used the default (typically
32K or 64K); most real applications use far smaller block sizes (2K or less)
with much less throughput. Coretest also reads only a single data stream many
times, thus compounding the error.

As far as increasing performance, adding software disk cache can often
increase performance in real terms. I've used the smartdrv cache included
with Windows to good effect, but many flavors of disk cache exist.