Re: Periodic rant about SCHED_ULE

On 2023-03-30, Matthias Andree <mandree@FreeBSD.org> wrote:
> Am 30.03.23 um 20:50 schrieb Mateusz Guzik:
>
>> Anyhow after sending the above e-mail an actual solution hit me: the X
>> server can tell the kernel what processes connect to it over the unix
>> socket, which again very well may be good enough.
>> 
>> In the reports I got I found pulseaudio, this one may need to be
>> patched in a similar manner.
>
> Pulseaudio shouldn't need such stuff since it would either try to go 
> into a real-time scheduling group (which I don't think SCHED_ULE would 
> have), or do a (privileged) renice -11 to have considerable priority 
> over non-privileged stuff. At least on Linux, that is.
>

From what I get, it seems most people with professional audio are
using JACK, and JACK runs in rtprio by default:

UID  PID PPID  C PRI NI     VSZ     RSS MWCHAN   STAT TT        TIME COMMAND
1100 1404 1403  2 -51  0  153508   71816 sigwait  I<s   -     1:28.97 /usr/local/bin/jackd -r

With the other aspects, I think there are two different
issues. One issue is that compute jobs do not always get
their fair timeshare - this is concerning servers with
batch compute load: I need such tasks to complete within
precalculated time, and that does not always happen now.

The other is about interactivity scoring etc., and that concerns
mainly desktop systems, and I think that is a bit more difficult to
get proper.