Re: [ANNOUNCE] 3.8-rc6-nohz4

[Steven Rostedt]

On Thu, 2013-02-07 at 17:41 +0100, Frederic Weisbecker wrote:

> I'm not convinced that "single task" must be a fundamental component
> of this. It's an implementation detail. We should be able to keep the
> tick off in the future when more than one task are on the runqueue and
> hrtick is on. May be this will never show up as a performance gain but
> we don't know yet.
> 
> Ok let's talk about that single task constraint in the Kconfig help so
> that the user knows the practical constraint as of today. But I
> suggest we keep that as an internal detail that we can deal with in
> the future.

Hmm, but isn't time slices still implemented by ticks? I would think
implementing multiple tasks would be another huge change.

Maybe have:

NO_HZ_IDLE
NO_HZ_SINGLE_TASK
NO_HZ_MULTI_TASK
NO_HZ_COMPLETE

And as Ingo has suggested, maybe in the future we can remove SINGLE and
MULTI and have just COMPLETE.

But anyway, the current method has a strict requirement of a single
task, and that is user visible. I would want to keep the config name
implying that requirement.

-- Steve


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/