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kalex
Mar 20, 2008, 06:26 AM
Hello,

I got my MBA about a week ago and haven't really used macbooks before. I have a Mac Pro and never put it to sleep.

How does sleep work on MBA? is the battery drained during sleep? if so how much? does it go into deep sleep - ie hibernation?
I use to have a dell laptop and always hibernated it but never slept it.

Is there a way to change the way sleep behaves on macbooks?


what do people use - sleep or hibernation?


sorry for so many questions, just trying to figure which option to use.

So far I had MBA for about a week and love it.


thanks

Alex



darwiniandude
Mar 20, 2008, 07:06 AM
Hi Alex. Most people use sleep on their Macs. Historically Macs have had more robust sleep and power management.

When you shut the lid or manually sleep a macbook, it is like suspend on a PC, not hibernate. Hd spins down, screen goes off, battery power holds ram contents. Atleast, that used to be the case...

What recent mac notebooks do is great. When you shut the lid or manually sleep, it first dumps the ram to a 2gb file on the disk, like hibernate. But it doesn't power off the machine. It sleeps it, using the battery to keep the contents in ram. This means you can open the lid and keep working instantly, far quicker than hibernate. But, it does use a little battery power.

The advatage is that if the battery does go flat, you don't lose what you were working on. You can also type a command into Terminal that changes the sleep mode, so you can get other behavior if you so desire.
I have mine set to not save the 2gb to disk.

twynne
Mar 20, 2008, 07:12 AM
Just wanted to add here for anyone interested, there's a great free extension out now called SmartSleep (link (http://www.versiontracker.com/dyn/moreinfo/macosx/33996)) which automatically decides between normal and 'safe' sleep based on the percentage (configurable) of battery remaining when you put the machine to sleep. This means if you have plenty of battery left or you're plugged in, sleep and resume are lighting fast.

I've been using it for a few weeks now and have had no issues whatsoever.

kalex
Mar 20, 2008, 09:40 AM
darwiniandude - Thank you for great explanation. Do you happen to know how much power actually drains from it while its sleeping with ram on? Also is there a way to switch to hibernate only? instead of first sleep then hibernate?




twynne - thanks for the link, I'll try it today.


Alex

twynne
Mar 20, 2008, 11:53 AM
darwiniandude - Thank you for great explanation. Do you happen to know how much power actually drains from it while its sleeping with ram on? Also is there a way to switch to hibernate only? instead of first sleep then hibernate?
Alex

SmartSleep will let you choose the sleep mode as well. It installs as a preference panel. :)

kalex
Mar 20, 2008, 03:12 PM
I don't think i like the sleep options. My battery was at 56% before I went to bed and I closed the lid of the laptop. just turned it back on and battery was at 21%. Is there a way i can enable hibernation mode to kick in and totally suspend ram to drive every time i close the lid? i don't mind waiting few seconds for it to restore RAM state, at least there is no drain on battery.


Thanks


Alex

kalex
Mar 20, 2008, 03:46 PM
Answered my own question. DeepSleep widget works great. I just reversed its purpose. instead of clicking on the widget to activate deep sleep, i set the main function to deep sleep and widget to safe sleep.

Thanks everybody for your help.

Alex