Choosing A Stripe-Size (RAID5 Array)

[Rishi Chopra]

I've had a tough time getting help for this question on the newsgroups and
freebsd.org discussion forums, so I thought I'd mail the list...

I'm setting up a 600GB Raid-5 array (4-200GB 8MB Buffer IDE disks connected
to an Adaptec 2400A controller) and would like some help picking a
stripe-size (this is the smallest unit of data written to each disk by the
raid controller.)  My usage pattern is fileserver and webserver+db, some
light desktop usage as well.  I'll be using defaults for the file system
(16K block size.)

Based on experience, can anyone suggest a good stripe-size choice?  Also, if
this controller performs best with a particular stripe-size under FreeBSD
(due to driver design, etc.) please say so; I can always tweak the newfs
command line switches to accomodate a particular stripe-size choice.

Please CC me on any response, as I am not a regular list subscriber.

-Rishi
rchopra at cal.berkeley.edu