1CPU Accounting Controller 2------------------------- 3 4The CPU accounting controller is used to group tasks using cgroups and 5account the CPU usage of these groups of tasks. 6 7The CPU accounting controller supports multi-hierarchy groups. An accounting 8group accumulates the CPU usage of all of its child groups and the tasks 9directly present in its group. 10 11Accounting groups can be created by first mounting the cgroup filesystem. 12 13# mkdir /cgroups 14# mount -t cgroup -ocpuacct none /cgroups 15 16With the above step, the initial or the parent accounting group 17becomes visible at /cgroups. At bootup, this group includes all the 18tasks in the system. /cgroups/tasks lists the tasks in this cgroup. 19/cgroups/cpuacct.usage gives the CPU time (in nanoseconds) obtained by 20this group which is essentially the CPU time obtained by all the tasks 21in the system. 22 23New accounting groups can be created under the parent group /cgroups. 24 25# cd /cgroups 26# mkdir g1 27# echo $$ > g1 28 29The above steps create a new group g1 and move the current shell 30process (bash) into it. CPU time consumed by this bash and its children 31can be obtained from g1/cpuacct.usage and the same is accumulated in 32/cgroups/cpuacct.usage also. 33