|Control Groupstats is inspired by the discussion at
|http://lkml.org/lkml/2007/4/11/187 and implements per cgroup statistics as
|suggested by Andrew Morton in http://lkml.org/lkml/2007/4/11/263.
|Per cgroup statistics infrastructure re-uses code from the taskstats
|interface. A new set of cgroup operations are registered with commands
|and attributes specific to cgroups. It should be very easy to
|extend per cgroup statistics, by adding members to the cgroupstats
|The current model for cgroupstats is a pull, a push model (to post
|statistics on interesting events), should be very easy to add. Currently
|user space requests for statistics by passing the cgroup path.
|Statistics about the state of all the tasks in the cgroup is returned to
|NOTE: We currently rely on delay accounting for extracting information
|about tasks blocked on I/O. If CONFIG_TASK_DELAY_ACCT is disabled, this
|information will not be available.
|To extract cgroup statistics a utility very similar to getdelays.c
|has been developed, the sample output of the utility is shown below
|~/balbir/cgroupstats # ./getdelays -C "/sys/fs/cgroup/a"
|sleeping 1, blocked 0, running 1, stopped 0, uninterruptible 0
|~/balbir/cgroupstats # ./getdelays -C "/sys/fs/cgroup"
|sleeping 155, blocked 0, running 1, stopped 0, uninterruptible 2