ProstGreSQL on RAID Question

Hi all,

I have set up a RAID-5 (soft RAID) arrray on my Linux machine, consisting of 5
18 GB UltraSCSI-2 (80 MB/sec) drives. Everythinng is working but I would like
to know, where I can tweak this for optimum performance.

The HOWTO, I found, said to set this up using a 32 KB chunk size for the 4 KB
ext2 filesystems. I know that PostGreSQL is using 8 KB blocks, should it
therefore not be better to set up the array, using 8 KB chunks? Or should I
increase the chunk size?

The array is only for use by the $PGDATA directory, nothing else will go
there, so this can be optimized for PG without any  consideration for
anything else.

Any input welcome.

Best regards,
Chris