Re: [PATCH] N1int for interactivity

[Con Kolivas <kernel@kolivas.org>]

On Wed, 16 Jul 2003 01:23, Felipe Alfaro Solana wrote:
> On Tue, 2003-07-15 at 05:55, Con Kolivas wrote:
> > I've modified Mike Galbraith's nanosleep work for greater resolution to
> > help the interactivity estimator work I've done in the O*int patches.
> > This patch applies to any kernel patched up to the latest
> > patch-O5int-0307150857 which applies on top of 2.5.75-mm1.
> >
> > Please test and comment, and advise what further changes you think are
> > appropriate or necessary, including other archs. I've preserved Mike's
> > code unchanged wherever possible. It works well for me, but n=1 does not
> > a good sample population make.
> >
> > The patch-N1int-0307151249 is available here:
> > http://kernel.kolivas.org/2.5
>
> I can still starve XMMS on 2.5.75-mm1 + patch-O5int-0307150857 +
> patch-N1int-0307152010:
>
> 1. Log on to KDE
> 2. Launch Konqueror
> 3. Launch XMMS and make it play
> 4. Move Konqueror window all over the desktop
>
> Step 4 will make XMMS starve for a few seconds. Also, under heavy load
> (while true; do a=2; done), moving the Konqueror window like crazy makes
> X go jerky after a few seconds. If I quit moving windows around, after a
> few other seconds, X returns to normal/smooth behavior.

I was more concerned to see if the N1 patch added anything to the current 
behaviour, but that is abandoned work now so don't worry. I can address these 
further issues incrementally if you're willing to test them. My test boxes 
have been tamed but I need and appreciate greatly your testing.

> I can fix the starvation/smoothness by setting:
>
> #define PRIO_BONUS_RATIO        45
> #define INTERACTIVE_DELTA       4
> #define MAX_SLEEP_AVG           (HZ)
> #define STARVATION_LIMIT        (HZ)
>
> For me, 2.6.0-test1 stock scheduler plus above changes makes the most
> user-friendly desktop I've ever seen.

With a max sleep avg of just one second you'll never starve X or xmms for 
sustained periods; but under load X will not be smooth getting jerky even 
with small bursts of heavy X use; that's why Ingo increased the max sleep avg 
in the first place... but that led to other issues...

Con