On Fri, 15 Oct 2004, Manuel Bouyer wrote:

> Date: Fri, 15 Oct 2004 21:29:33 +0200
> From: Manuel Bouyer <bouyer@antioche.eu.org>
> To: Karl Janmar <karl@utopiafoundation.org>
> Cc: tech-kern@NetBSD.org
> Subject: Re: ATI IXP IDE chipset support
>
> On Fri, Oct 15, 2004 at 02:50:27PM +0200, Karl Janmar wrote:
> > >
> > > You can also try the attached program:
> > > ./tst /dev/rwd0d 30000
> > > (increase the second parameter if it completes in less than 2 seconds)
> > > This will benchmark the bandwith available between the drive's cache and
> > > the host (as opposed to the overall drive performances).
> > >
> >
> > This is with the SATA disk:
> > # ./tst /dev/rwd1d 3000
> > 9673491 us, 19.382868 MB/s
> >
> > This is on the ATA disk:
> > # ./tst /dev/rwd0d 3000
> > 53188011 us, 3.525231 MB/s
>
> these are really poor performances, something is wrong.
> >From a seagate 8G drive (ST38410A) connected to a i810 controller:
> rochebonne# /tmp/tst /dev/rwd0d 3000
> 4577374 us, 40.962351 MB/s
>
> >
> > these results are a little bit strange(for me as I am not an expert),
> > because  I get this when using dd, /mnt is on wd0e (the ATA disk):
> > # dd if=/dev/zero of=/mnt/apslask bs=4096 count=100000
> > 100000+0 records in
> > 100000+0 records out
> > 409600000 bytes transferred in 17.693 secs (23150398 bytes/sec)
> >
> > This doesn't ofcourse exacly test the same thing but....
>
> This is a 400MB file, if I got it right. Could it fit entirely in RAM ?

I got 512MB of RAM in that machine, so yes?
But if I issue a sync(8) it doesn't delay more then 1/2 second or so.
Doesn't that mean that the data found it's way all the way to the disk
cache?

- Karl