We pretend we have one head with two megabyte worth of sectors per cylinder.
The code try to access another head in what it belives to the same
physical cylinder, because it belives that it would be faster than
waiting for the next free sector under this head to come around.
Most modern drives doesn't have a "classical" geometry, and thus
we end up fooling ourselves doing the above optimization. With this
change we will fill a cylinder sequentially if we can, and thus get
much more mileage from the track-buffer/cache built into the drives.
As a result a lot of seeks to the next or previous track should be
avoided by this.
(My disk is a lot less noisy actually...)
You can still get the old behaviour, by specifying zero for the
numbers.
This will also solve the problem with newfs barfing at really big
drives.
Obtained from: adult advice from Kirk.
most common cd9660 and nfs options like God intended them. (It is now
possible to say
mount -o ro,soft,bg,intr there:/foo/bar /foo/bar
again.) This whole getmntopt() business is an incredible botch;
it never should have been anything more than a wrapper around
getsubopt(3). Because if the way the current hackaround is implemented,
options which take arguments (like the old `rsize' and `wsize') are still
unavailable, and must be accessed the new, broken way.
(It's unimaginable how Berkeley managed to screw up one of the few things
about NFS that Sun actually got right to begin with!)
being output if <= 1 rpos; there is a bug in the kernel which doesn't
quite get along with this. Changed default #rpos to 1, and fixed up
manual page. Converted nrpos to 1 if user specifies 0.
the use of the rotational position table.
2) Allow specification of 0 rotational positions (disables function).
3) Make rotdelay=0 and nrpos=0 by default.
The purpose of the above is to optimize for modern SCSI (and IDE) drives
that do read-ahead/write-behind.
