Re: Cheetah vs. UDMA: Bonnie says UDMA is faster! why?

Gerard Roudier (groudier@club-internet.fr)
Thu, 26 Mar 1998 21:43:28 +0100 (MET)


On Thu, 26 Mar 1998, Leonid Kalmankin wrote:

>
>
> > Seagate Cheetah (10K RPM UW-20):
> >
> > -------Sequential Output-------- ---Sequential Input-- --Random--
> > -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> > Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> > 100 2134 94.7 6018 78.1 3199 70.5 2361 90.8 9999 89.6 140.9 17.2
>
> Well, something is definitely wrong with your setup, hw or sw.

Seems it is the system memory bandwitch, or the CPU speed.

> What kind of SCSI controller are you using?
> Here are results for my Cheetah, old model, UW, 20 Mhz and BusLogic 958 -

Better to upgrade the system hardware, IMO, in order to get full
throughput for the Cheetah.

> and i think you can get even more from Cheetah.A
> System has 128M of RAM, hence -s 256.
>
> -------Sequential Output-------- ---Sequential Input-- --Random--
> -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> 256 8571 93.2 12741 50.6 4594 29.8 9925 73.6 13321 20.5 106.7 2.1

If you want to send benchmark results, please, add an accurate description of
the system on which the benchmark has been ran, otherwise your posting
would just be confusing stuff.

Just a question: are you ready to give money back to people who bought
the same controller as yours because of your posting and who did'nt notice
any performance difference ? ;-)

Gerard.

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