On Tue, 11 Oct 2011 19:15:29 +0300 "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> wrote: > Every task_struct has timer_slack_ns value. This value uses to round up > poll() and select() timeout values. This feature can be useful in > mobile environment where combined wakeups are desired. > > Originally, prctl() was the only way to change timer slack value of > a process. So you was not able change timer slack value of another > process. > > cgroup subsys "timer_slack" implements timer slack controller. It > provides a way to set minimal timer slack value for a group of tasks. > If a task belongs to a cgroup with minimal timer slack value higher than > task's value, cgroup's value will be applied. > > Timer slack controller allows to implement setting timer slack value of > a process based on a policy. For example, you can create foreground and > background cgroups and move tasks between them based on system state. I'm having trouble understanding the value of this feature. Users can presently control the timer-slack of a group of processes via inherit-over-fork. Perhaps there's a case for providing a way for process A to set process B's slack. And perhaps B's children. That would be a simpler patch and would have the considerable advantage that it doesn't require cgroups. So.... why should we merge this? -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
