On Mon, Oct 18, 2004 at 11:07:18PM +0200, Karl Janmar wrote:
> > 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?

Yes, it should. Hum, could you try reading a file (after making sure it's
not any more in cache) ? Myabe it's slow in only one direction ..

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--