Re: Regression seen for patch "sched:dont decrease idle sleep avg"
From: Tim Chen
Date: Tue May 16 2006 - 20:08:09 EST
On Tue, 2006-05-16 at 09:45 +1000, Con Kolivas wrote:
> Yes it's only designed to detect something that has been asleep for an
> arbitrary long time and "categorised as idle"; it is not supposed to be a
> priority stepping stone for everything, in this case at MAX_BONUS-1. Mike
> proposed doing this instead, but it was never my intent.
It seems like just one sleep longer than INTERACTIVE_SLEEP is needed
kick the priority of a process all the way to MAX_BONUS-1 and boost the
sleep_avg, regardless of what the prior sleep_avg was.
So if there is a cpu hog that has long sleeps occasionally, once it woke
up, its priority will get boosted close to maximum, likely starving out
other processes for a while till its sleep_avg gets reduced. This
behavior seems like something to avoid according to the original code
comment. Are we boosting the priority too quickly?
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/