linux-kernel - Re: RSDL v0.31

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Message-Id: <200703210715.35898.a1426z@gawab.com>
Date:	Wed, 21 Mar 2007 07:15:35 +0300
From:	Al Boldi <a1426z@...ab.com>
To:	Artur Skawina <art_k@...pl>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: RSDL v0.31

Artur Skawina wrote:
> Al Boldi wrote:
> > --- sched.bak.c	2007-03-16 23:07:23.000000000 +0300
> > +++ sched.c	2007-03-19 23:49:40.000000000 +0300
> > @@ -938,7 +938,11 @@ static void activate_task(struct task_st
> >  				     (now - p->timestamp) >> 20);
> >  	}
> >
> > -	p->quota = rr_quota(p);
> > +	/*
> > +	 * boost factor hardcoded to 5; adjust to your liking
> > +	 * higher means more likely to DoS
> > +	 */
> > +	p->quota = rr_quota(p) + (((now - p->timestamp) >> 20) * 5);
> >  	p->prio = effective_prio(p);
> >  	p->timestamp = now;
> >  	__activate_task(p, rq);
>
> i've tried this and it lasted only a few minutes -- i was seeing
> mouse cursor stalls lasting almost 1s. i/o bound tasks starving X?
> After reverting the patch everything is smooth again.

This patch wasn't really meant for production, as any sleeping background 
proc turned cpu-hog may DoS the system.

If you like to play with this, then you probably want to at least reset the 
quota in its expiration.


Thanks!

--
Al

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