freebsd 13 ryzen micro stutter

[Nils B.]

On 25.03.21 16:31, Andriy Gapon wrote:
> [...]
> There are some tools in tools/sched/ directory.
> schedgraph.py can be used for visual inspection of scheduling traces collected
> using KTR.  The file has instructions on how to collect them.
> Alternatively, schedgraph.d can be used to collect such traces.
> If anyone affected can gather a short sample that captures the problem, then
> there might be someone who would be willing to look at them.

what should I tell? I've set "kern.sched.steal_thresh: 0 -> 2" and reliably got that
micro-suttering back while watching YouTube videos (tearing test i.e.).

Then I loaded kernel modules "dtrace.ko" and "dtraceall.ko" and ran

	./schedgraph.d > /tmp/sched.out

The micro-stuttering immediately went away while above DTrace-script was running.
So it seems that the light load of the running DTrace-script was enough to eliminate
any micro-stutterings.


I've uploaded resulting .ktr- and .out-files (for both steal_thresh=2/0) here:

	kern.sched.steal_thresh=2
	-------------------------
		http://156.67.189.93:9080/sched.steal2.txz


	kern.sched.steal_thresh=0
	-------------------------
		http://156.67.189.93:9080/sched.steal0.txz


Haven't tried your mentioned first KTR-variant yet...



Thanks and BR,
Nils