On Fri, 2013-03-08 at 15:30 +0800, Michael Wang wrote: > On 03/08/2013 02:44 PM, Mike Galbraith wrote:
> > In general, I think things would work better if we'd just rate limit how > > frequently we can wakeup migrate each individual task. > > Isn't the wakeup buddy already limit the rate? and by turning the knob, > we could change the rate on our demand. I was referring to the existing kernel, not as altered. > We want > > jabbering tasks to share L3, but we don't really want to trash L2 at an > > awesome rate. > > I don't get it..., it's a task which has 'sleep' for some time, unless > there is no task running on prev_cpu when it's sleeping, otherwise > whatever the new cpu is, we will trash L2, isn't it? I'm thinking if you wake it to it's old home after a microscopic sleep, it has a good chance of evicting the current resident, rescuing its L2. If tasks which do microscopic sleep can't move around at a high rate, they'll poke holes in fewer preempt victims. If they're _really_ fast switchers, always wake affine. They can't hurt much, they don't do much other than schedule off. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
