On Sun, 16 Dec 2007 22:00:23 -0500 (EST) Parag Warudkar <[EMAIL PROTECTED]> wrote:
> In my quest to get the wake-ups from idle per second down to bare minimum, > I noticed 3 places in the kernel that could benefit from > using init_timer_deferrable() instead of init_timer() - > > a) drivers/net/sky2.c - watchdog_timer. This was showing up high on > Powertop's list of things that cause routine wakeups from idle. After > converting to init_timer_deferrable() the wakeups went down and this one > no longer shows up in powertop's list. 25% reduction. > > b) kernel/time/clocksource.c - watchdog_timer - same story as sky2.c > > c) net/core/neighbour.c - gc_timer - Most benefit from deferrable timer. neigh_periodic_timer() is actually doing almost nothing per round, since it looks only one slot of hash table. We could probably convert it to a workqueue and scan whole table at once. > > I am running a kernel with above changes and haven't noticed any immediate > problems and the wakeups-from-idle have gone down from 5-7 to mere 1-2 per > second. > > Is there any reason not to make the above timers deferrable - corner > cases, other side effects? If not then I will submit a patch. > > Thanks > > Parag > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
