Re: performance -cfs19 vs. -ck1 for 2.6.22

Ingo Molnar
2007-07-16T08:56:08Z

* Ni@m <niam.niam@gmail.com> wrote:

> Hi, Ingo!
>
> >>Could you run the
> >>following script:
> >> http://people.redhat.com/mingo/cfs-scheduler/tools/cfs-debug-info.sh
> I'll do that! But a little bit later - I have tested that on my home
> computer.
>
> >>hm, is there no other workload on the system?
> Workload: firefox, transmission(torrent client), gnome terminal, music
> player.
>
> Now I think it could be not a scheduler issue but network subsystem
> ... but I've got such situation on previous kernels and w/o torrent
> client running.
>
> The problem is not in switching tabs in firefox but in
> _opening_new_url_. I'm not good in Con's patches but are they touching
> network subsystem?

Con's patches are not really touching the network subsystem, but we want
to analyze this and figure out where the difference in behavior comes
from, be that scheduling, networking or something else.

to help us figure out the nature of the delay, could you do another
thing as well:

strace -ttt -TTT -f -o firefox.trace.txt -p `pidof firefox-bin`

this will produce firefox.trace.txt - compress that via bzip -9. (and
send that file privately - it might include private information embedded
in URLs, etc.) Please do such a trace both under CFS and under -ck,
under similar circumstances.

To isolate it down to the CPU scheduler changes you can create a pure
2.6.22+SD kernel by applying this patch to a vanilla v2.6.22 tree:

http://kernel.org/pub/linux/kernel/people/ck/patches/2.6/2.6.22/2.6.22-ck1/patches/sched-staircase-deadline-cpu-scheduler.patch

Ingo