>
> I didnt dare try an ffs with 1meg blocks and 128k fragments and
> 2-block readahead: would that have worked?
not.

it's fact that netbsd NEEDs change to have MAX_IO not 64k but at least 1MB
for todays hardware.
todays drives which can do 42MB/s (real data tested with 7200rpm fujitsu)
and 7ms see can read 300kB/s in one seek time.