Why the niceness is not always taken into account ?

[Alexandre Laurent]

I do not want to touch the kernel at all. I was giving the information 
about cgroups since it was one of the question asked before. I 
understood that the SCHED_AUTOGROUP is not using at all cgroups.

My question was more like : is there a way (like giving hint) to ask 
the autogroup system to group two SSH sesssions in order to get nice 
behaving as expected without disabling the whole autogroup system.

Le 18.04.2013 17:32, Valdis.Kletnieks at vt.edu a écrit :

> On Thu, 18 Apr 2013 16:57:41 +0200, Alexandre Laurent said:
>
>> Note : the cgroups are not mounted at all.
>
> The cgroups filesystem doesn't have to be mounted for that - the 
> kernel
> handles that internally.
>
>> I still have a little question about it : Is it possible to force 
>> the
>> grouping of specific tasks ? (Which could be better than just 
>> disabling
>> the feature)
>
> At that point, you're better off mounting the cgroups filesystem and
> using
> something like systemd to put tasks into cgroups and control them. 
> It's
> a Really Bad Idea to try to handle that in-kernel. SCHED_AUTOGROUP 
> relies
> on the fact that many heavy-load processes are launched from xterms, 
> so
> grouping "everything in each xterm" into a separate group and then 
> one
> group
> for everything launched from the desktop works pretty well. and is 
> really
> bog-simple to code. Trying to do anything more complicated in-kernel 
> will
> be a mess, because nobody agrees on a policy that should be used 
> (other
> than
> the one used by AUTOGROUP)