Re: [PATCH v4] sched: automated per session task groups

Paul Turner
2010-12-03T08:37:54Z

On Thu, Dec 2, 2010 at 10:48 PM, Mike Galbraith <efault@gmx.de> wrote:
> On Thu, 2010-12-02 at 21:11 -0800, Paul Turner wrote:
>> On 11/30/10 22:16, Mike Galbraith wrote:
>> > On Tue, 2010-11-30 at 19:39 -0800, Paul Turner wrote:
>> >> On 11/28/10 06:24, Mike Galbraith wrote:
>> >>>
>> >>> Something else is seriously wrong though.  36.1 with attached (plus
>> >>> sched, cgroup: Fixup broken cgroup movement) works a treat, whereas
>> >>> 37.git and tip with fixlet below both suck rocks.  With a make -j40
>> >>> running, wakeup-latency is showing latencies of>100ms, amarok skips,
>> >>> mouse lurches badly.. generally horrid.  Something went south.
>> >>
>> >> I'm looking at this.
>> >>
>> >> The share:share ratios looked good in static testing, but perhaps we
>> >> need a little more wake-up boost to improve interactivity.
>> >
>> > Yeah, feels like a wakeup issue.  I too did a (brief) static test, and
>> > that looked ok.
>> >
>> >     -Mike
>> >
>>
>> Hey Mike,
>>
>> Does something like the below help?
>
> Unfortunately not.  For example, Xorg+mplayer needs (30 sec refresh)..
>
>  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  P COMMAND
>  6487 root      20   0  366m  30m 5100 S   31  0.4   2:04.83 2 Xorg
>  4454 root      20   0  318m  28m  15m S   29  0.4   0:38.06 3 mplayer
>
> ..but gets this when a heavy kbuild is running along with them.
>
>  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  P COMMAND
>  6487 root      20   0  366m  30m 5136 S   12  0.4   2:25.98 1 Xorg
>  5595 root      20   0  318m  28m  15m R    8  0.4   0:09.31 3 mplayer
>
> There are 4 task groups active at this time, Xorg, mplayer, Amarok and
> konsole where the kbuild is running make -j40.
>

Hmm.. unfortunate. Ok -- based on the traces of synthetic loads and
the traces of their share on wake-up I think this is the right track
at least, will refine it tomorrow.

Thanks for trying it.

>        -Mike
>
>
>