Re: SATA RAID, tested again, blaming IRQs

[Alan Cox <alan redhat com>]

On Wed, Apr 07, 2004 at 07:16:48AM -0400, Neal Becker wrote:
> AFAICT, software raid is great.  It is far more flexible than hardware raid.  
> Obviously, there is some load on the CPU, but I'm taking a wild guess that 
> the extra load is minimal over the interrupt load that already would be 
> needed for disk I/O.

For raid1 the killer is PCI bus bandwidth - twice the data. Some of the
newer SATA hardware is getting quite smart at being neither hw or sw raid 
but a good hybrid. That may well kill off old "smart" hw raid.

Alan