On Thu, Jun 20, 2002 at 11:24:33PM +0200, Manuel Bouyer <bouyer@antioche.eu.org> wrote:
> On Thu, Jun 20, 2002 at 05:15:49PM -0400, John Franklin wrote:
> > Why do we want to tie priorities to anything other than an abstraction of
> > priorities?  That is, why not make an n-queue system in which queue 0 has
> > the highest priority and must be cleared before anything on queue 1 can
> > be serviced, then queue 2, dot dot dot, then queue n.  Then provide
> 
> No, there needs to be some limit for each queue, otherwise we can end up
> with requests in lower priority queue never been serviced. I was thinking
> at something more like proportional priorities (queue 1 gets serviced 1
> time when queue 0 gets 2 times, or something like that).

I would think that priority reversal may be able to help there.  If a
request wasn't completed within certain amount of time (different for
each queue, I'd think) then move that request into a higher-priority
queue. This way we can guarantee that even lowest-priority requests
will eventually be served. 

--Artem