On Thu, Apr 17, 2003 at 02:52:13PM -0400, Chuck Yerkes wrote:
> > be connected to a Ultra320 controller. I could as well use 20 U320 drives
> > connected to 4 U320 controller, and it would still be faster.
> > Also, in my setup I can have 20 * 256 = 5120 outstanding commands.
> > With an external RAID this would be limited to 256.
> 
> I'm not sure I'd put 20 drives on a single PCI bus.  U320 is fine,
> but PCI is smaller unless you have PCI/100 - only now becoming
> common.

This alpha has 2 64bit PCI busses

> 
> > hardware RAID PCI controllers don't have the limitations of external raid
> > boxes, as they have mutliple channels. So they should be at last as fast as
> > software RAID.
> 
> But then you have a controller locked inside a box.  And configured.
> Take a hit on that box, and you're screwed.

I wouldn't use such hardware in critical boxes without a spare :)

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 24 ans d'experience feront toujours la difference
--