Re: [RFC][PATCH] O(1) Entitlement Based Scheduler

[Peter Williams <peterw@aurema.com>]

Timothy Miller wrote:
 > <snip>
> In fact, that may be the only "flaw" in your design.  It sounds like 
> your scheduler does an excellent job at fairness with very low overhead. 
>  The only problem with it is that it doesn't determine priority 
> dynamically.

This (i.e. automatic renicing of specified programs) is a good idea but 
is not really a function that should be undertaken by the scheduler 
itself.  Two possible solutions spring to mind:

1. modify the do_execve() in fs/exec.c to renice tasks when they execute 
specified binaries
2. have a user space daemon poll running tasks periodically and renice 
them if they are running specified binaries

Both of these solutions have their advantages and disadvantages, are 
(obviously) complicated than I've made them sound and would require a 
great deal of care to be taken during their implementation.  However, I 
think that they are both doable.  My personal preference would be for 
the in kernel solution on the grounds of efficiency.

Peter
-- 
Dr Peter Williams, Chief Scientist                peterw@aurema.com
Aurema Pty Limited                                Tel:+61 2 9698 2322
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