Subject: Re: Slow 486 seems really slow
To: Frederick Bruckman <fb@enteract.com>
From: Ken Nakata <nakata@sequent.com>
List: port-i386
Date: 02/14/2000 19:32:22
Frederick Bruckman wrote:
> 
> On Mon, 14 Feb 2000, Jonathan R. Hinds wrote:
> 
> > dmesg says the follow about the controller and hard drive:
> >
> > wdc0 at isa0 port 0x1f0-0x1f7 irq 14
> > wd0 at wdc0 channel 0 drive 0: <QUANTUM FIREBALL1280A>
> > wd0: drive supports 8-sector pio transfers, lba addressing
> > wd0: 1222MB, 2484 cyl, 16 head, 63 sec, 512 bytes/sect x 2503872 sectors
> > wd0: drive supports PIO mode 4, DMA mode 2
> >
> > Does this mean that it is using DMA? I guess that I will try another hard
> > drive and see what happens.
> 
> Guess so. I would try "de-rating" to DMA mode 1, in the kernel config,
> to try and work around the bug. PIO mode 3, DMA mode 1 is plenty fast,
> if it works.

Hmm, this line here from dmesg:

> > wdc0 at isa0 port 0x1f0-0x1f7 irq 14

It's got no dma channel assigned.  Only an irq channel.  Even so, do you
still get DMA transfer?

Ken