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Subject: Re: kern.sched.quantum: Creepy, sadistic scheduler
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On Tue, 17 Apr 2018 09:05:48 -0700
Freddie Cash <fjwcash@gmail.com> wrote:

> # Tune for desktop usage
> kern.sched.preempt_thresh=3D224
>=20
> =E2=80=8BWorks quite nicely on a 4-core AMD Phenom-II X4 960T Processor
> (3010.09-MHz K8-class CPU) running KDE4 using an Nvidia 210 GPU.

For interactive tasks, there is a "special" tunable:
% sysctl kern.sched.interact
kern.sched.interact: 10 # default is 30
% sysctl -d kern.sched.interact
kern.sched.interact: Interactivity score threshold

reducing the value from 30 to 10-15 keeps your gui/system responsive,
even under high load.