Fedora 14 under constant load

[Adam Williamson]

On Fri, 2010-10-15 at 10:47 -0600, Orion Poplawski wrote:
> On 10/14/2010 05:58 PM, Jesse Keating wrote:
> > -----BEGIN PGP SIGNED MESSAGE-----
> > Hash: SHA1
> >
> > On 10/14/2010 04:49 PM, John Poelstra wrote:
> >> That's what's so mysterious, very little CPU time or activity.
> >
> > I saw this at one point, and the kernel folks found it to be a load
> > balancing thing gone awry in the kernel.
> >
> > 2.6.35.6-33.rc1 seems to include a patch:
> >
> > - - Add sched-35-increment-cache_nice_tries-only-on-periodic-lb.patch,
> > another fix for excessive scheduler load balancing.
> >
> > That should be in kernel-2.6.35.6-39.fc14, which is in dist-f14.  My
> > load went down and the laptop (also an M1330) has cooled down a bit, but
> > it is still above one usually.
> 
> With 2.6.35.6-43.fc14.i686.PAE, after letting the machine quiet down a bit 
> after logging in and starting up Firefox and Thunderbird:
> 
> 
> top - 10:45:59 up 8 min, 14 users,  load average: 0.81, 1.65, 1.12
> Tasks: 184 total,   2 running, 182 sleeping,   0 stopped,   0 zombie
> Cpu(s):  2.0%us,  0.8%sy,  0.0%ni, 97.0%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st
> 
> Top causes for wakeups:
>    40.6% (117.7)   [kernel scheduler] Load balancing tick
>    29.8% ( 86.4)   firefox
>     5.9% ( 17.1)   konsole
>     5.4% ( 15.6)   PS/2 keyboard/mouse/touchpad interrupt
>     3.7% ( 10.7)   thunderbird-bin
>     3.6% ( 10.5)   [ata_piix] <interrupt>
> 
> Actually moving the mouse and typing seems to bring the load back up to 1. 
> Never saw it go below .8

Now I actually look at the load stats, I do seem to have something like
this problem, I just never noticed (I thought Poelcat was talking about
CPU load % at first):

[adamw at adam ~]$ uptime
 10:06:28 up  1:00,  2 users,  load average: 0.77, 0.76, 0.81

on a system where all I've done is booted and sat on IRC in a meeting
for that hour, using Firefox but nothing super crazy.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Fedora Talk: adamwill AT fedoraproject DOT org
http://www.happyassassin.net