Some "/sys" entries exceeds buffer size.
This results to some statistics loss ('BlkIO' in particular):

 wc -c /sys/fs/cgroup/blkio/lxc/alt/blkio.throttle.io_service_bytes
 318 /sys/fs/cgroup/blkio/lxc/alt/blkio.throttle.io_service_bytes
Signed-off-by: Denis Pynkin <dans@altlinux.org>