I set up a couple of partitions to perform raw I/O to, one on the RAID-5 drive
and one on the RAID-0 drive:
dd to raw device:
RAID-5: 6.4MB/s
RAID-0: 9.1MB/s
There is *no* difference between 3.9 and 4.0-beta.
For kicks, I also tested reading from a raw device:
dd reading from a raw device:
RAID-5: 38.3MB/s
RAID-0: 81.4MB/s
For what it's worth, the numbers for writing and reading are identical under
linux too.
Summary: hw-raid controllers are slow for writing, at least without a cache
battery.
last question: what kind of performance can I expect if I get the battery?
Rob Urban
