Re: gradual timeofday overhaul

[George Anzinger]

Chris Friesen wrote:
> George Anzinger wrote:
>
> > Well, that is part of the accounting overhead the increases with 
> > context switch rate.  You also need to include the time it takes to 
> > figure out which of the time limits is closes (run time limit, profile 
> > time, slice time, etc).  Then, you also need to remove the timer when 
> > switching away.  No, it is not a lot, but it is way more than the 
> > nothing we do when we can turn it all over to the periodic tick.  The 
> > choice is load sensitive overhead vs flat overhead.
>
>
> It should be possible to be clever about this.  Most processes don't use 
> their timeslice, so if we have a previous timer running, just keep track 
> of how much beyond that timer our timeslice will be.  If we context 
> switch before the timer expiry, well and good.  If the timer expires, 
> set it for what's left of our timeslice.

Me thinks that rather quickly devolves to a periodic tick.

--
George Anzinger   george@xxxxxxxxxx
High-res-timers:  http://sourceforge.net/projects/high-res-timers/

-
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/