TTY task group scheduling

Lucius Windschuh lwindschuh at
Thu Nov 18 19:21:46 UTC 2010

2010/11/18 Andriy Gapon <avg at>:
> [Grouping of processes into TTY groups]
> Well, I think that those improvements apply only to a very specific usage pattern
> and are greatly over-hyped.

But there are serious issue if you use FreeBSD as a desktop OS with
SMP and SCHED_ULE, or?
Because currently, my machine is barely usable if a compile job with
parallelism is running. Movies stutter, Firefox hangs. And even nice
-n 20 doesn't do the job in every case, as +20 seems not to be the
idle priority anymore?!?
And using "idprio 1 $cmd" as a workaround is, well, a kludge.
I am not sure if TTY grouping is the right solution, if you look at
potentially CPU-intensive GUI applications that all run on the same
TTY (or no TTY at all? Same problem).
Maybe, we could simply enhance the algorithm that decides if a task is
interactive? That would also improve the described situation.



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