[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1261133658.14314.33.camel@localhost>
Date: Fri, 18 Dec 2009 11:54:18 +0100
From: Kasper Sandberg <lkml@...anurb.dk>
To: Mike Galbraith <efault@....de>
Cc: Ingo Molnar <mingo@...e.hu>,
Jason Garrett-Glaser <darkshikari@...il.com>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
LKML Mailinglist <linux-kernel@...r.kernel.org>,
Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: x264 benchmarks BFS vs CFS
On Thu, 2009-12-17 at 14:30 +0100, Mike Galbraith wrote:
> On Thu, 2009-12-17 at 12:00 +0100, Kasper Sandberg wrote:
> > On Thu, 2009-12-17 at 11:53 +0100, Ingo Molnar wrote:
> > > * Jason Garrett-Glaser <darkshikari@...il.com> wrote:
> > >
> > > > On Thu, Dec 17, 2009 at 1:33 AM, Kasper Sandberg <lkml@...anurb.dk> wrote:
> > > > > well well :) nothing quite speaks out like graphs..
> > > > >
> > > > > http://doom10.org/index.php?topic=78.0
> > > > >
> > > > >
> > > > >
> > > > > regards,
> > > > > Kasper Sandberg
> > > >
> > > > Yeah, I sent this to Mike a bit ago. Seems that .32 has basically tied
> > > > it--and given the strict thread-ordering expectations of x264, you basically
> > > > can't expect it to do any better, though I'm curious what's responsible for
> > > > the gap in "veryslow", even with SCHED_BATCH enabled.
> > > >
> > > > The most odd case is that of "ultrafast", in which CFS immediately ties BFS
> > > > when we enable SCHED_BATCH. We're doing some further testing to see exactly
> >
> > Thats kinda besides the point.
> >
> > all these tunables and weirdness is _NEVER_ going to work for people.
>
> Fact is, it is working for a great number of people, the vast majority
> of whom don't even know where the knobs are, much less what they do.
but not as great as it could be :)
>
> > now forgive me for being so blunt, but for a user, having to do
> > echo x264 > /proc/cfs/gief_me_performance_on_app
> > or
> > echo some_benchmark > x264 > /proc/cfs/gief_me_performance_on_app
>
> Theatrics noted.
>
> > just isnt usable, bfs matches, even exceeds cfs on all accounts, with
> > ZERO user tuning, so while cfs may be able to nearly match up with a ton
> > of application specific stuff, that just doesnt work for a normal user.
>
> Seems you haven't done much benchmarking. BFS has strengths as well as
> weaknesses, all schedulers do.
yeah, BFS just has more strengths and fewer weaknesses than CFS :)
>
> > not to mention that bfs does this whilst not loosing interactivity,
> > something which cfs certainly cannot boast.
>
> Not true. I sent Con hard evidence of a severe problem area wrt
> interactivity, and hard numbers showing other places where BFS needs
> some work. But hey, if BFS blows your skirt up, use it and be happy.
Theatrics noted.
As for your point, well.. as far as i have heard, all you've come up
with is COMPLETELY WORTHLESS use cases which nobody is ever EVAR going
to do, and thus irellevant
>
> -Mike
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists