Phil Mendelsohn <mend0070 at tc.umn.edu> writes:

> On Fri, 25 May 2001, Florin Iucha wrote:
> 
> > On Fri, May 25, 2001 at 08:46:59AM -0700, AAAunderground wrote:
> > > >    The reasoning I follow is this. If we take the example of a record
> > > > (as in LP, vinyl), a point in the outside moves faster relative to a
> > > > point closer to the center. If hard drives were vinyl LPs, I would want
> > > 
> > > That was the case with older drives. But definately all new drives have
> > > a design built into them that allow the drive to spin at the same speed
> > > thoughout the platter. Unfortunatly I can not think of the name of the
> > > technology that allows this right now. It is the same thing that is used
> > > in cdroms for the same purpose. So to answer the question , no it
> > > doesn't matter on a performance or accesibility level where you store
> > > crucial files.
> 
> No, I don't believe that's correct.  Linear track speed varies because
> rotational speed is constant on HDs.  A 7200rpm drive isn't 6000-8200, it
> stays put.
> 
> The first time I ran into variable speed was when Apple put it on the
> original Mac 3.5 floppy, I think.

One of the reasons that hard-drives don't use variable speed is it's
too slow to change the rotational speed of the platters.  Compared to
how fast the access arm can seek.  It'd slow things down too much.
-- 
David Dyer-Bennet      /      Welcome to the future!      /      dd-b at dd-b.net
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