> 
> I'm using an interleave of 512, although I have no idea how good or
> bad that really is. The ccd(4) manpage would suggest 171, since that
> appears to be the (real) track size (1026 sec/cyl, 6 heads), but that
> seemed too odd a number to use.

there is no real track size in new drives as tracks holds more or less
data depending of placement.

use LARGE values, and if you use lfs, try to place lfs partition aligned
to lfs big block (1M default) and set ccd stripe size equal to it. then
one lfs write will hit exactly one disk