turned off sleep image (2gb reclaimed) - a bit worried

Discussion in 'MacBook Air' started by sir. mac, Feb 21, 2008.

  1. sir. mac macrumors regular

    Joined:
    Nov 21, 2006
    #1
    Just followed these instructions here to turn off the sleep image and let the machine write to memory in sleep mode. This reclaimed 2gb on my MBA and I was happy as a puppy :p

    Now whenever I let the machine sleep, every few minutes the logo on the back flashes up for a short while, like it´s waking up. Is this supposed to happen?

    Also, could there be some permanent disk damage if the battery runs out while the machine is in sleep mode now?
     
  2. Salty Pirate macrumors 6502

    Salty Pirate

    Joined:
    Oct 5, 2005
    Location:
    kansas city
    #2
    I let the machine run out of battery to see what would happen and the machine shuts down when 1 minute was left. I shut the machine and charged it, to my surprise I opened it and it came up just fine.

    As for the flashing, that is not normal. Have you re-booted and tryed it or re0-set the smu or pmu or whatever it is called? The other thing you could try is create a test account, put the machine to sleep and see if the behavior manifests itself. If it does, I would say it is apple store time.
     
  3. BryanLyle macrumors 6502a

    BryanLyle

    Joined:
    Aug 2, 2005
    #3
    Once you make this change, can you go back to hibernate mode 3 ? If so, how do you do it?
     
  4. clayj macrumors 604

    clayj

    Joined:
    Jan 14, 2005
    Location:
    visiting from downstream
    #4
    Just run this command in Terminal:

    Code:
    sudo pmset -a hibernatemode 3
     
  5. sir. mac thread starter macrumors regular

    Joined:
    Nov 21, 2006
    #5
    Seems fine after the reboot. Good to hear that it won´t melt my machine, thanks for the info :)
     
  6. raremage macrumors 6502a

    Joined:
    Nov 21, 2005
    Location:
    Orlando, Florida
    #6
    FYI there is a nice article on how sleep mode works here.
     
  7. sir. mac thread starter macrumors regular

    Joined:
    Nov 21, 2006
    #7
    Thanks! But now the battery seems to drain more during sleep, anyone else notice this or is it just my imagination? Will come back later with some tests on this.
     
  8. sir. mac thread starter macrumors regular

    Joined:
    Nov 21, 2006
    #8
    yup, seems like it drains more battery whence in mode-o:

    # 0 - Old style sleep mode, with RAM powered on while sleeping, safe sleep disabled, and super-fast wake.
    # 1 - Hibernation mode, with RAM contents written to disk, system totally shut down while “sleeping,” and slower wake up, due to reading the contents of RAM off the hard drive.
    # 3 - The default mode on machines introduced since about fall 2005. RAM is powered on while sleeping, but RAM contents are also written to disk before sleeping. In the event of total power loss, the system enters hibernation mode automatically.
     
  9. Spievy macrumors regular

    Joined:
    Dec 24, 2002
    Location:
    Virginia
    #9
    Very interesting, I had no idea. I am assuming this works on all intel macs?
     
  10. raremage macrumors 6502a

    Joined:
    Nov 21, 2005
    Location:
    Orlando, Florida
    #10
    I wonder why it drains more in mode 0 versus mode 3?

    Other than the power to write the memory to disk initially, i wouldn't expect that - I was under the impression the functionality would be identical.
     

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