Re: [patch] CFS (Completely Fair Scheduler), v2

[Gene Heskett <gene.heskett@gmail.com>]

On Tuesday 17 April 2007, Ingo Molnar wrote:
>* Ingo Molnar <mingo@elte.hu> wrote:
>> ok - fortunately the delta between -v2-rc0 and -v2-final is pretty
>> small. One difference is the child-runs-first fix. To restore the
>> parent-runs-first logic, do this:
>>
>> 	echo 0 > /proc/sys/kernel/sched_child_runs_first
>>
>> does this make any difference?
>
>ok, i've got something better to test: i separated the delta out into a
>more finegrained stack of 3 patches. You can pick them up from:
>
> http://redhat.com/~mingo/cfs-scheduler/older/sched-cfs-v2-rc0.patch
> http://redhat.com/~mingo/cfs-scheduler/older/sched-cfs-v2-rc0-preempt-fix.p
>atch
> http://redhat.com/~mingo/cfs-scheduler/older/sched-cfs-v2-rc0-child-runs-fi
>rst.patch
> http://redhat.com/~mingo/cfs-scheduler/older/sched-cfs-v2-rc0-misc.patch
>
Ahh, so many cats, and so few recipes here Ingo.  In this case cats=patches & 
recipes=time to test adequately.  I do have another box, but it would 
probably take a week & about a big buck to get that old rh7.3 brought up to 
date & suitable, and its only a 500MHZ K-III, which might make the diffs more 
obvious.  It would need a video card to replace its dinosaur Diamond and a 
fresh dvd drive.  And its motherboard has very buggy usb chips.  TYAN S-1590.  
Never could get anything bigger than a mouse packet through them.

>i test-built and test-booted all 4 steps of this. The baseline -v2-rc0
>patch should be the one that works - you might want to double-check it,
>just to be sure. One of the other 3 patches ontop of this baseline
>causes the regression on your desktop. My current bet is on preempt-fix,
>so i have put that one first. The other one would be the second patch,
>child-runs-first. The misc patch should have no effect on behavior - but
>i've included it for completeness. (and i was wrong about the 'nice
>fix', it is not in this delta)
>
>	Ingo



-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Q:	What's the difference between a dead dog in the road and a dead
	lawyer in the road?
A:	There are skid marks in front of the dog.