busy hard disk = no response

[Marc Lucke]

I seem to have to use libata & ata_piix to be able to boot with by sata 
disk.  Performace isn't as wonderful as the late 2.4 series kernels 
where my sata disk was seen as hde but it is passable.  However with the 
non-scsi driver I could use hdparm to unmask interrupt request - i.e. 
allow the computer to keep doing something else if it has a very busy 
drive and I can't do that with hdparm now.  Is there a scsi 
alternative?  Otherwise my web, smtp, ssh - everything - goes down the 
toilet everytime my disk gets too busy.

note: in an earlier post I thought this might have to do with swap - I 
don't think so anymore about being told about swapiness.