Re: Interactivity improvements

[Mike Fedyk <mfedyk@matchmail.com>]

On Wed, Aug 06, 2003 at 02:48:11PM -0400, Timothy Miller wrote:
> The idea I'm proposing, however poorly formed, is that if we allow some 
> "excessive" oscillation early on in the life of a process, we may be 
> able to more quickly get processes to NEAR its correct priority, OR get 
> its CPU time over the course of three times being run for the 
> underdamped case to be about the same as it would be if we knew in 
> advance what the priority should be.  But in the underdamped case, the 
> priority would continue to oscillate up and down around the correct 
> level, because we are intentionally overshooting the mark each time we 
> adjust priority.
> 
> This may not be related, but something that pops into my mind is a 
> numerical method called Newton's Method.  It's a way to solve for roots 
> of an equation, and it involved derivatives, and I don't quite remember 
> how it works.  But in any event, the results are less accurate than, 
> say, bisection, but you get to the answer MUCH more quickly.

Sounds interesting.

Much like a decaying average, or average over the entire lifetime of the
process which can be weighed into the short term interactivity calculations
also.

I think Con is working on something like this already, except that it's
taking the short term into account more than the long term.