In Message <41EF6A34.3040708@netbsd.ro> ,
   Mihai CHELARU <kefren@netbsd.ro> wrote:

=>Manuel Bouyer wrote:
=>> Note that, with this hardware configuration, you can't even paralelize
=>> accesses to the hardware, because you have 2 disks per IDE channel (so
=>> some access have to be serialized). Things would be a bit better if you could
=>> have one disk per channel (for each write, you have to write data and
=>> partity, at last if those can be paralelized, you get soome performance
=>> boost).
=>
=>True, but even in this case I should expect the performance to be near 
=>the performance one hard disk has, isn't it ?

   Not really, since you end up having to seek the data disk, write
the data block, seek the parity disk, and write the parity block.
If you had separate controllers for the data and parity disks the
seeks and writes could be done concurrently.

					Gary D. Duzan