Re: [RFC] sched: The removal of idle_balance()

From: Mike Galbraith
Date: Fri Feb 15 2013 - 02:26:28 EST

On Fri, 2013-02-15 at 01:13 -0500, Steven Rostedt wrote:

> Think about it some more, just because we go idle isn't enough reason to
> pull a runable task over. CPUs go idle all the time, and tasks are woken
> up all the time. There's no reason that we can't just wait for the sched
> tick to decide its time to do a bit of balancing. Sure, it would be nice
> if the idle CPU did the work. But I think that frame of mind was an
> incorrect notion from back in the early 2000s and does not apply to
> today's hardware, or perhaps it doesn't apply to the (relatively) new
> CFS scheduler. If you want aggressive scheduling, make the task rt, and
> it will do aggressive scheduling.

(the throttle is supposed to keep idle_balance() from doing severe
damage, that may want a peek/tweak)

Hackbench spreads itself with FORK/EXEC balancing, how does say a kbuild
do with no idle_balance()?


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at