Re: [patch] CFS (Completely Fair Scheduler), v2

From: Peter Williams
Date: Tue Apr 17 2007 - 10:05:34 EST


Ingo Molnar wrote:
* William Lee Irwin III <wli@xxxxxxxxxxxxxx> wrote:

On Tue, Apr 17, 2007 at 04:46:57PM +1000, Peter Williams wrote:

Have you considered using rq->raw_weighted_load instead of rq->nr_running in calculating fair_clock? This would take the nice value (or RT priority) of the other tasks into account when determining what's fair.
I suspect you mean (curr->load_weight*delta_exec)/rq->raw_weighted_load in update_curr().

good idea, i'll try that.

In the longer term, I'd suggest modifying this idea to use the maximum of rq->raw_weighted_load and a running average of rq->raw_weighted_load much the same as was done within the load balancer code. This will tend to make scheduling "smoother". To try the idea out you could (on an SMP system) use one of the rq->cpu_load[] metrics as the running average.

Peter
--
Peter Williams pwil3058@xxxxxxxxxxxxxx

"Learning, n. The kind of ignorance distinguishing the studious."
-- Ambrose Bierce
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