Re: disk head scheduling

Rik van Riel (riel@nl.linux.org)
Thu, 18 Mar 1999 23:46:50 +0100 (CET)

On Thu, 18 Mar 1999, Arvind Sankar wrote:
> On Thu, Mar 18, 1999 at 10:52:44PM +0100, Ingo Molnar wrote:
> > On Thu, 18 Mar 1999, Arvind Sankar wrote:
> >
> > the sorting (the elevator algorithm) is per-device. The queue is
> > technically one queue, but thats just an implementation matter. (and of
> > course it matters in the case when we hit the queue length limit)
>
> ah. But it is per major-device linking. It would be nice to have per physical
> device linking, then we could do a two-way elevator algorithm.

A two-way elevator? We don't need/want that. For one, a
full seek only takes as long as some 5 t-t-t seeks.
Secondly, just how do you plan on letting the disk spin
backwards?

Rik -- Open Source: you deserve to be in control of your data.
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