Re: PROBLEM: high load average when idle

[Arjan van de Ven <arjan@linux.intel.com>]

Linus Torvalds wrote:
> 
> I wonder if the whole "round_jiffies()" thing should be written so that it 
> never rounds down, or at least never rounds down to before the current 
> second!

that's what it is supposed to do already...

166
167         if (j <= jiffies) /* rounding ate our timeout entirely; */
168                 return original;
169         return j;
170 }

so there is always a gap of at least 1 jiffie no matter what


> 
> I have to say, I also think it's a bit iffy to do "round_jiffies()" at all 
> in that per-CPU kind of way. The "per-cpu" thing is quite possibly going 
> to change by the time we actually add the timer, so the goal of trying to 
> get wakeups to happen in "bunches" per CPU should really be done by 
> setting a flag on the timer itself - so that we could do that rounding 
> when the timer is actually added to the per-cpu queues!

it's pretty much the same thing though