Ultra ATA card doesn't seem to provide Ultra speeds.

[Bruce Cran]

On Thu, Jul 31, 2003 at 06:33:28PM -0600, soralx at cydem.org.ua wrote:
> 
> > > Maybe not, but they do give a transferspeed from medium range and that
> > > is what can be expected.
> >
> > Hmm, I guess not everyone does that. We have some seagates here at work we
> > were wondering about because they seemed too slow, and we couldn't find
> > anything aside from what we already knew... the tranfer speed of the
> > SCSI interface, which is basically from drive cache to controller. That is
> > unless the manufacturers hide the info somewhere so you really have to
> > dig, which wouldnt' surprise me.
> 
> Example took me less than 64 seconds to find (for Seagate Barracuda IV):
> http://www.seagate.com/cda/products/discsales/personal/family/0,1085,559,00.html
> Look for 'Avg. Sustained Transfer Rate'. AFAIK, every manufacturer I know
> gives the sustained transfer rate specs (which are sometime a bit too high than
> in reality). If the specs are not specified, it'd be very suspicious, and I
> would think 128 time before buying such drives.
> 

The transfer rates are usually given for the outside of the disk I think. 
Speeds usually drop about 15-20MB/s between the outside and
inside.   If you've got FreeBSD 5.1, you can use the 'diskinfo -t <disk>' 
command to measure the performance of the hard drive.   It should be a little
more accurate than using dd, because I'm guessing the reads/writes don't go
through the vfs layer.

--
Bruce Cran