Subject: Re: RAID In general (Re: Hot Swappable IDE Kits)
To: Chuck Yerkes <firstname.lastname@example.org>
From: Manuel Bouyer <email@example.com>
Date: 04/20/2003 13:30:35
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
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 <firstname.lastname@example.org>
NetBSD: 24 ans d'experience feront toujours la difference