Kirill,
> 1. what kernel do you use?
 2.6.18 + ovz028stab047.1 

> 2. how do you decide that your machine is idling?
>    can you please provide output of `ps axf` from HN?
 this sounds like philosophical question, howether - I created this machine
for compilation and load testing, so when I'm not loading it with anything,
it should be idling, and I confirm this with top/munin stats;)

> 3. what do you mean by "I played with adding/removing cpus from the guest"?
>    vzctl set <VEID> --cpus <N>  or something else?
 Yes, I started with 8, and then did load testing with varying number of
cpus, this includes reducing number of cpus while the jobs are running
(which btw, results in 'top' and similiar tools failing with:
"top: failed /proc/stat read",  strange that noone noticed this until now)

 The problem also goes away after I remove limits from number of cpus and
do some load testing, but this takes multiple hours (and in the meantime
guest that should be reporting load hovering in 0.2 ~ 1.0 range reported
load ~ 1500 ).
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