On Fri 2014-06-06 10:59:13, Wang, Yalin wrote: > Hi Pavel, > > > This is kernel log from a Android phone: > > <6>[ 7262.353794] PM: suspend exit 2014-05-07 21:19:17.438320072 UTC > <6>[ 7262.353820] PM: suspend entry 2014-05-07 21:19:17.438348353 UTC > <6>[ 7264.822367] PM: suspend exit 2014-05-07 21:19:19.906892259 UTC > <6>[ 7264.822391] PM: suspend entry 2014-05-07 21:19:19.906919447 UTC > <6>[ 7266.100346] PM: suspend exit 2014-05-07 21:19:21.184872206 UTC > <6>[ 7266.100371] PM: suspend entry 2014-05-07 21:19:21.184899342 UTC > <6>[ 7268.650852] PM: suspend exit 2014-05-07 21:19:23.735377778 UTC > <6>[ 7268.650876] PM: suspend entry 2014-05-07 21:19:23.735404393 UTC > <6>[ 7269.023665] PM: suspend exit 2014-05-07 21:19:26.398622725 UTC > <6>[ 7269.023691] PM: suspend entry 2014-05-07 21:19:26.398651787 UTC > <6>[ 7269.232675] PM: suspend exit 2014-05-07 21:19:28.959217201 UTC > <6>[ 7269.250878] PM: suspend entry 2014-05-07 21:19:28.977414076 UTC > <6>[ 7269.256004] PM: suspend exit 2014-05-07 21:19:28.982547202 UTC > <6>[ 7269.260040] PM: suspend entry 2014-05-07 21:19:28.986580588 UTC > <6>[ 7269.265169] PM: suspend exit 2014-05-07 21:19:28.991711785 UTC > <6>[ 7269.269311] PM: suspend entry 2014-05-07 21:19:28.995851004 UTC > <6>[ 7270.410962] PM: suspend exit 2014-05-07 21:19:30.137503920 UTC > <6>[ 7270.410986] PM: suspend entry 2014-05-07 21:19:30.137529389 UTC > <6>[ 7272.970123] PM: suspend exit 2014-05-07 21:19:32.696662461 UTC > <6>[ 7272.973330] PM: suspend entry 2014-05-07 21:19:32.699869909 UTC > <6>[ 7275.534527] PM: suspend exit 2014-05-07 21:19:35.261069387 UTC > <6>[ 7275.534551] PM: suspend entry 2014-05-07 21:19:35.261095846 UTC > <6>[ 7275.556227] PM: suspend exit 2014-05-07 21:19:35.282769491 UTC > <6>[ 7275.579152] PM: suspend entry 2014-05-07 21:19:35.305686210 UTC > <6>[ 7275.822618] PM: suspend exit 2014-05-07 21:19:37.918187092 UTC > <6>[ 7275.822644] PM: suspend entry 2014-05-07 21:19:37.918215894 UTC > <6>[ 7276.122721] PM: suspend exit 2014-05-07 21:19:40.479243344 UTC > <6>[ 7276.122745] PM: suspend entry 2014-05-07 21:19:40.479269125 UTC > <6>[ 7278.578212] PM: suspend exit 2014-05-07 21:19:42.934733395 UTC > <6>[ 7278.578237] PM: suspend entry 2014-05-07 21:19:42.934761520 UTC > > You can see there is several times suspend / resume status change > Form 2014-05-07 21:19:28. 959217201 to 2014-05-07 21:19:28.995851004 > > There is also some suspend fail in this log , the suspend return -EBUSY > Because of driver wake up system during suspend process . > > During our power test , suspend frequently like this will consume more > Power , because it will suspend/resume lots of > Devices . Why don't we make a time window to make sure there is no more than > 1 time suspend during the time window ? If you can optimize power consumption on your hardware, by all means go ahead. But arbitrary limit "don't suspend more than twice a second" is probably not a way to go... not without some analysis. You may want to take a look at n900 -- it uses regular idle, not suspend, to save power. > I remember Android use wakelock for suspend in older linux kernel , > The wakelock will make some time window check to make sure > Not suspend frequently , could autosleep also add this ? Are you sure autosleep does not already have equivalent functionality? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
