Re: Re: [REGRESSION] [Linux 3.2] top/htop and all other CPU usage

[Michal Hocko <mhocko@suse.cz>]

On Tue 29-11-11 11:38:47, Artem S. Tashkinov wrote:
> On Nov 29, 2011, Michal Hocko <mhocko@suse.cz> wrote: 
>  
> > As I have written in other email could you post your config and collect
> > the following data?
> > for i in `seq 30`; 
> > do 
> >         cat /proc/stat > `date +'%s'`
> >         sleep 1
> > done
> > export old_user=0 old_nice=0 old_sys=0 old_idle=0 old_iowait=0; 
> > 
> > # for all your available CPUs
> > grep cpu0 * | while read cpu user nice sys idle iowait rest; 
> > do 
> >         echo $cpu $(($user-$old_user)) $(($nice-$old_nice)) $(($sys-$old_sys)) $(($idle-$old_idle)) $(($iowait-$old_iowait))
> >         old_user=$user old_nice=$nice old_sys=$sys old_idle=$idle old_iowait=$iowait
> > done
> 
> 1322566208:cpu0 5199 0 2931 357890604 2541
> 1322566209:cpu0 0 0 1 0 0
> 1322566210:cpu0 0 0 0 0 0
> 1322566211:cpu0 0 0 0 0 0
> 1322566212:cpu0 0 0 0 0 0
> 1322566213:cpu0 0 0 0 0 0
> 1322566214:cpu0 1 0 0 0 0
> 1322566215:cpu0 2 0 0 0 0
> 1322566216:cpu0 3 0 0 0 0
> 1322566217:cpu0 2 0 0 0 0
> 1322566218:cpu0 4 0 0 0 0
> 1322566219:cpu0 1 0 0 0 0
> 1322566220:cpu0 2 0 0 0 0
> 1322566221:cpu0 2 0 1 0 0
> 1322566222:cpu0 1 0 0 0 0
> 1322566223:cpu0 2 0 0 0 0
> 1322566224:cpu0 1 0 1 0 0
> 1322566225:cpu0 1 0 0 0 0
> 1322566226:cpu0 2 0 0 0 0
> 1322566227:cpu0 1 0 1 0 0
> 1322566228:cpu0 2 0 0 0 0
> 1322566229:cpu0 2 0 0 0 0
> 1322566230:cpu0 6 0 3 0 0
> 1322566231:cpu0 1 0 0 0 0
> 1322566232:cpu0 2 0 0 0 0
> 1322566233:cpu0 3 0 0 0 0
> 1322566234:cpu0 2 0 0 0 0
> 1322566235:cpu0 2 0 2 0 0
> 1322566236:cpu0 0 0 1 0 0
> 1322566237:cpu0 1 0 0 0 0

Hmm, really strange. It looks that idle/iowait is not accounted at
all. Which would explain why the numbers you are seeing are so weird.


> 
> $ grep . -r /sys/devices/system/cpu/cpuidle/
> /sys/devices/system/cpu/cpuidle/current_driver:intel_idle
> /sys/devices/system/cpu/cpuidle/current_governor_ro:menu

I will check whether I have a machine with intel_idle somewhere around.

> 
> $ grep . -r /sys/devices/system/cpu/cpufreq/
> /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate_min:10000
> /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate:10000
> /sys/devices/system/cpu/cpufreq/ondemand/up_threshold:95
> /sys/devices/system/cpu/cpufreq/ondemand/sampling_down_factor:1
> /sys/devices/system/cpu/cpufreq/ondemand/ignore_nice_load:0
> /sys/devices/system/cpu/cpufreq/ondemand/powersave_bias:0
> /sys/devices/system/cpu/cpufreq/ondemand/io_is_busy:1
> 
> One thing I have to note, it takes some time (from 30 seconds to 10
> minutes) before this bug starts manifesting itself.




-- 
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9    
Czech Republic