* Arjan van de Ven <arjan@xxxxxxxxxxxxx> [2009-03-05 16:14:51]: > On Wed, 4 Mar 2009 17:42:49 +0530 > Arun R Bharadwaj <arun@xxxxxxxxxxxxxxxxxx> wrote: > > With the timers queued I measure the sleep state residency > > for a period of 10s. > > Next, I enable timer migration and measure the sleep state > > residency period. > > is your table in seconds? Because realistically, at least on PC like > hardware, doing work to get sleep times over a 100 / 200 msecs or so > isn't going to save you any amount of measurable power anymore... > Hi Arjan, Yes, the table is in seconds. Rather than looking at timer migration as a direct means of obtaining power savings, I would like to see it as one of the mechanisms which would aid in preventing an almost idle cpu from waking up unnecessarily, thereby causing power penalty. Otherwise, there is a chance of all the CPUs in a particular package being idle and the entire package going into deep sleep. So we cannot really get big power savings just by doing timer migration alone. --arun > > > -- > Arjan van de Ven Intel Open Source Technology Centre > For development, discussion and tips for power savings, > visit http://www.lesswatts.org _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
