Re: [RFC v2 4/7] change kernel accounting to include steal time

Peter Zijlstra
2010-09-03T07:19:13Z

On Thu, 2010-09-02 at 15:19 -0300, Glauber Costa wrote:
> So what's the big drawback of just making sched_clock return sched_clock_unstolen?
> When there is no steal time involved, they will just be equal anyway.
> And this way, everybody that relies on sched_clock for whatever reason,
> will probably work.

Because there's a number of things wanting sched_clock() and the likes
to be synchronized across cpus, its impossible to make _unstolen()
synchronized because different vcpus can get different service levels.

Also, I think you want to keep measuring scheduling latency and other
such things in actual wall-time.