Sleeping consumes lots of battery?

Discussion in 'MacBook Pro' started by thefoo, Jul 8, 2007.

  1. thefoo macrumors member

    Jun 9, 2007
    Yesterday I called Apple about my new MBP (15" 2.4). I have it on AC power at home, I flip the lid down around midnight with the battery at 100% charged.

    The next day after work I open it up to find the charge way down. Apple suggested I calibrate the battery which I did yesterday.

    So last night it hit 100% and I closed the lid, the power LED began doing it's usual "snore" dimming thing. Eleven hours later, I return and it's at 78% full.

    Does eleven hours in sleep really take 22% of the battery??? Before I calibrated it had lost around 75% of battery after being in sleep mode for 36hrs roughly.
  2. kolax macrumors G3

    Mar 20, 2007
    I noticed mine runs down a bit too - although I can't understand why.

    Mac's offer 2 sleep modes - safe sleep (where all contents in RAM are written to the hard drive so you don't loose any data if the battery runs out) and normal sleep (where if you lost power, you'd lose everything hadn't saved).

    Safe sleep is on by default, and from the definition, it shouldn't use any power; where normal sleep will.

    You're not alone anyway.
  3. thefoo thread starter macrumors member

    Jun 9, 2007
    Yeah I heard there are two sleep modes. I can't find them in System Preferences to switch between them though.

    So essentially if your MBP is sleeping you're going to need to fully-charge it every two-three days to keep it going?
  4. Mac-Addict macrumors 65816


    Aug 30, 2006
    Yep when my MBP sleep on battery it drains my battery overnight to around 20% from full.
  5. EspressoLove macrumors 6502


    Jun 29, 2007
    Bay Area
    It's actually two in one ....

    It's actually two in one .... sort of :
    (by default (and you can not find it in System Prefs)) it's set to "safe sleep", and it does both : write RAM to HDD, and still keeps it in RAM.
    So if battery still has charge when you wake it, it springs from RAM, if it drained it's supposed to be reloaded from HDD (this failed on me (SR MBP) once I tried this).

    I personally have it to sleep old mode, without writing to HDD, on windows I used it for years, and it works for me on Mac.
    My reason I dont' want to wait, and also risk my HDD, as been the case.

    Of course saving your "state" just in case is good thing, but having my Macs crash on my geeky switcher soul several times in one month I've been switcheroo, I just learned to not trust :p, preconfigured, "dubmb proof", "just works" solutions, and retracted to caring about my work myself.
    It's the same old zeros and ones, regardles windoze or mac'ky, so the robust workflows just the same, although I do manage to enjoy goodies of OS X & my MBP ;))))
  6. EspressoLove macrumors 6502


    Jun 29, 2007
    Bay Area
    I keep my MBP connected all the time, so can not measure how "sleep" drains the battery, and there's no need for me at the moment to care if it drains battery too much.

    But for those of you who need equivalent of windoze "hibernate" (dump to HDD, RAM switched off - so drastic decrease in energy drain), I suggest you search these forums and web, there definitely has to be a solution, as I easly found a way to switch off default "safe sleep".

    But, on second thought, you have to be windoze/hacky soul enough, because most probably you'll have to go to terminal, and not be scared of risk of screwing things, and also forgetting about "just works" slotutions/attitude :rolleyes:.
  7. DavoMrMac macrumors 6502


    Oct 9, 2005
    I think a lot of people do not notice this because they are in one of two scenarios.

    They use their MBPro all day, then maybe a little in the evening, then sleep it and charge it overnight so it is ready for the next day.

    Or, they use it when out and about on battery, then switch to mains when in the office/home.

    It is not often I would leave mine in sleep and not charging. The only time I did, I noticed that it used a fair bit of battery. Original MBPro CoreDuo, so a while back.
  8. zenigra macrumors newbie

    Jul 8, 2007
    Set Hibernation mode

    read this...
    it is really helpfull
  9. mkrishnan Moderator emeritus


    Jan 9, 2004
    Grand Rapids, MI, USA
    Wow... I don't have a MBP, mind you, but this has never been normal for the G4 notebooks. iBooks with reasonably good-condition batteries would lose maybe 3-5% of battery life asleep overnight. I measured my battery loss rate in sleep as about 3% / 10 hours once, and that was about 1.5-2 years after I got my iBook. They're certainly able to be left asleep on battery for several days without dying (they don't have safe sleep, without hacks).

    So something sounds off to me about this....
  10. Abstract macrumors Penryn


    Dec 27, 2002
    Location Location Location
    The old PowerBooks lasted longer when in sleep mode, meaning they drained less battery power (although this could be due to me having more RAM than in my old PowerBook......I still have 2 sticks of RAM, but more of it).

    The new MacBooks and MBPs are a bit more "sophisticated" with their sleeping, but it also means more hiccups. Sometimes, my laptop wakes up from sleep, and all I get is a black screen. I never get to my login window, so I never actually get to my Desktop, and I need to hard restart my machine by holding on to the POWER button for 4-5 seconds. :mad:

    It never used to happen.
  11. pdra05 macrumors regular

    Apr 24, 2007
    Melbourne City, VIC, Australia
    Same here, I left my (3 day old) MacBook Pro on sleep mode during the night. Battery was 100% charged.. 10% was taken away during the night. So I guess it's normal then? This never happened when I was using my iBook G4.. :confused:
  12. devilot Moderator emeritus


    May 1, 2005
    I don't know much about this issue at all, and I rarely bother sleeping the MB or using it w/out it being plugged in, but the one time I did do so, I did notice a significant drop in battery life. A bit off-putting for sure.

    There is this rather detailed thread, too, for more reading.
  13. thefoo thread starter macrumors member

    Jun 9, 2007
    So by the looks of the links posted it's dumping RAM to disk in case of full power failure, while maintaining RAM electrically while it has power.

    I may just have to pmset -a 1 (it is currently 3) and check out my battery life later.

    I wonder how much power RAM consumes...
  14. thefoo thread starter macrumors member

    Jun 9, 2007
    Well, I just tried this. I opened the lid on returning and the screen showed that last image (safari) dimmed, with a progress bar along the bottom.

    Once loaded, the screen brightened up, but the mouse and keyboard were frozen hard. Nothing I could do but hold the power key down five seconds and reboot.

    After reboot, spotlight didn't work so had to reboot again.

    I prefer losing juice to a crashing system now..!
  15. soLoredd macrumors 6502a

    Mar 12, 2007
    The longest I've had my MB on sleep was ~24 hours. I slept it at 100% and when I returned from sleep it was about 88%. Granted, I didn't sleep with anything running, I even shut off AirPort (not sure if this matters or not). I'd say 99.3% of my use on my MB is when it's plugged in but when I do use battery, I think it performs pretty well. I definitely wouldn't want to change anything as far as the sleep setting, I think Apple gives us, my default, the best choice for the least compromise.
  16. Zadillo macrumors 65832

    Jan 29, 2005
    Baltimore, MD
    Just to be fair, this isn't unique the Apple portables. My Sony Vaio would significantly run down battery while sleeping as well.
  17. devilot Moderator emeritus


    May 1, 2005
    But these new Mac Intel portables run down the battery much more than the PPC Macs did. That's what bugs some of us. :p

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