At 02:45 PM 24/04/00 -0700, Gregory Leblanc wrote:
> > -----Original Message-----
> > From: Seth Vidal [mailto:[EMAIL PROTECTED]]
> > Sent: Monday, April 24, 2000 2:39 PM
> > To: [EMAIL PROTECTED]
> > Subject: celeron vs k6-2
> >
> >
> > Hi folks,
> > I did some tests comparing a k6-2 500 vs a celeron 400 - on a raid5
> > system - found some interesting results
> >
> > Raid5 write performance of the celeron is almost 50% better
> > than the k6-2.
> >
> > Is this b/c of mmx (as james manning suggested) or b/c of the FPU?
>
>NOT because of MMX, as the K6-2 has MMX instructions. It could be because
>of the parity calculations, but you'd need to do a test on a single disk to
>make sure that it doesn't have anything to do with the CPU/memory chipset or
>disk controller. Can you try with a single drive to determine where things
>should be?
This may indeed be because of the MMX instructions in the K6-2.
The MMX instructions in the K6-2 are SLOWER than the Intel counterparts.
The FPU is also slower. If you were able to use proper 3DNow! instructions
instead of MMX, you would notice a marked improvement in the K6-2's speed.
The K6-III improved this somewhat, but the performance of MMX instructions
didn't equal that of 3DNow! until the Athlon came along. You'll see this
sort of difference if you run something like rc5 key cracking on your
machine, as it has modes for using MMX or 3DNow! for its calculations.
--
-=[ Stuart Young (Aka Cefiar) ]=-------------------------------
| http://amarok.glasswings.com.au/ | [EMAIL PROTECTED] |
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