Adaptect raid performance with FreeBSD

[Raymond Wiker]

Ari Suutari writes:
 > dd if=/dev/rda1s1a of=/dev/null bs=1m count=100
 > 100+0 records in
 > 100+0 records out
 > 104857600 bytes transferred in 4.193832 secs (25002814 bytes/sec)
 > 
 > So, I get only about 25MB/s. Shouldn't I be getting something
 > like 70 MB/s, or even more since there are two disks that
 > can server read requests ?

        Have you tried other block sizes? I think you may be able to
get better results by going to a lower block size (e.g, 64k instead of
1m). Some experimentation will show which block size(s) work best.