Re: [RFC 4/8] Improve the tracking of active utilisation

From: Peter Zijlstra
Date: Wed Jan 27 2016 - 09:39:54 EST


On Wed, Jan 27, 2016 at 02:36:51PM +0100, Luca Abeni wrote:
> Ok, so I implemented this idea, and I am currently testing it...
> The first experiments seem to show that there are no problems, but I
> just tried some simple workload (rt-app, or some other periodic taskset
> scheduled by SCHED_DEADLINE). Do you have suggestions for more
> "interesting" (and meaningful) tests/experiments?

rt-app is the workload generator, right?

I think the most interesting part here is the switched_from path, so
you'd want the workload to include a !rt task that gets PI boosted to
deadline every so often.

Also, does rt-app let tasks die? Or does it spawn N tasks and lets them
run jobs until the end? I think you want to put some effort in
task_dead_dl() as well.

After that, just make sure rt-app generates a _lot_ of tasks such that
the migration thing gets used.

Other than that, no, not really :-)