Promise Ultra ATA 66 controller vs. FC1

[Alexander Dalloz]

Am Fr, den 23.01.2004 schrieb Robert D. Arendt um 19:18:
> Steve Saady wrote:
> > I have a Promise Ultra 66 eide controller, but think it is only being 
> > acessed at 33 Mhz.  I have looked around, but have not found how to 
> > ascertain what rate Fedora is using it at.
> > Is there a way to configure FC1 to use it at 66MHz?
> > 
> <snip>
> > 
> > dmesg|more :
> > ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
> > 
> I added idebus=66 to /etc/grub.conf, so my boot line now looks like:
>    kernel /vmlinuz-2.6.1-1.53smp ro root=LABEL=/ apm=off idebus=66
> should work with the nominal FC1 kernel as well.  Really boosted my
> disk I/O speed.
> 
> Hope this helps,
> -Bob Arendt

What kind of hardware are you running - no PC ware or even very old EISA
bus hardware?

idebus=66 is nonsense and might even be dangerous on normal PC hardware,
as simply the bus frequency is 33 MHz and nothing else!

How did you measure the speed boost? Please compare the speed at
idebus=33 and with your setting of idebus=66 and post your values and
how you measured the I/O speed values.

Alexander


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Alexander Dalloz | Enger, Germany
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