On Thu, Aug 5, 2010 at 4:03 PM, Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote: >> > so what would wake a phone up from suspend where the phone should go back to >> > sleep in under a second? >> >> Here are some real-world examples from shipped android devices: >> - battery gauging happens every 10 minutes, need to wake long enough >> to chatter with the 1w interface and make sure the battery is not >> exploding >> - always on mail/im/calendar/etc sync often has network events that >> happen every 5-10 minutes which cause devices to briefly wake up and >> return to sleep >> - gps tracker app might wake every couple minutes or every n gps >> events to log location >> - low power audio subsystems can wake you up every 1-4 seconds (pcm) >> or 1-4 minutes (mp3) to fetch more data > > Interesting! > > So for an mp3 playback, does an Android suspend between data fetches? It can if the latency is long enough (which is why I point out low power audio which is usually high latency). For low latency (system sounds, etc) 10-25ms between buffers it's not practical to fully suspend but we will go to the lowest power state in idle if possible. Brian _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
