@Sergey L , bumping this up, CloudLinux, if memory serves me right, isn't available for OpenVZ/Virtuozzo, so, maybe this feature can be introduced for CentOS and any/all other Linux distributions. We would use it by setting a percentage of the total CPU power each subscription can use in real time if under total load.
Not sure if that can be done in OpenVZ/Virtuozzo containers though.