Thanks for all the useful answers.  The server is currently running on a
RAID-1 set of SATA disks.  I chose to configure one big raid0 spanning the
entire disks though, for the comfort of having to manage only 1 raid set
(instead of raid0, raid1, raid2, ...), accepting the overhead of having to
resync the entire mirror after an unclean shutdown (though clean shutdowns
will unconfigure swap and leave the mirror in a consistent state).  

	Geert