Cylinder boundaries in 4.3BSD

[Doug Alan]

> What we do is make the disk look like an RA-81 or an RD-51.

That will work, but you still have the problem that your partitions
are not beginning at the beginning of cylinders.  This messes up the
Berkeley Fast File System's perfomance fine-tuning.

> If you make it look like an RD53, then you will still need the
> special disktab entry, but you won't have the benifit of separate h
> and g partitions.

I understand, but I don't want separate g and h partitions anyway, so
this is not a problem.

> Yet another possibility, if you don't really care about getting
> "standard" kernels to run on them, is to make it look like an rd51.
> rd51 is the type the controller returns if it can't determine the
> type.  That is what we do for almost all our large microvax disks.

If I don't care about getting standard kernals to run on them, I'd
just use my own customized partition table, and then I'd get the
fine-tuning right.  The question is how much will using a standard
partition table, which has not been customized for a nonstandard
drive, degrade system performance?  One percent?  Then, who cares.
Fifty percent?  Then, it's worth caring about.

|>oug /\lan