[oracle1]

Do the processor and hdd still run when a macbook is sleeping? I am wondering if it's ok to put a macbook in a sleeve/bag while its sleeping, or will it overheat without ventilation. Sorry if it's been asked a million times, I searched and didnt find an answer.

[amru]

i dont know if the processor/hdd is working or not.. but i know u can put it to sleep & carry it in a bag/sleeve, as long as the light is pulsing

[Bolero421]

The macbook has a fairly interesting sleep system, which is sort of a hybrid of regular and deep/hibernation sleep. When you close the lid, you will notice that the while power-indicator light will shine solid for several-many seconds. During this time, the current state of the computer is written to the RAM, which allows for a quick "reload" time upon awakening as well as requiring minimal power usage. However, macbooks (and I assume MBPs as well) also write the contents of the RAM to the hard drive. If you place your hand on or put your ear near the case you can feel/hear the hard drive spin up and then shut down as the data is written. Once your computer's state is stored in both RAM and on the hard drive, everything but the RAM is powered down and the status light will begin its "breathing" cycle.

So in short, no; once in sleep neither the processor nor hard drive are active. However, I have ran across a bug that I've heard confirmation of from others where something goes wrong with the SMS system during the sleep-preparation cycle (while the light is still solid) and it causes a kernal panic. It seems to be caused by excessive movement of the laptop before it fully enters sleep, and effectively cancels the operation. If you were to put your macbook into a case or bag after this happens, you would run the risk of overheating. I myself have pulled my macbook out of its case only to find it blazing hot with the fans running full-tilt (thankfully no damage).

And so the lesson is never put your laptop into a bag until you see the pulsing light.

[ibook_steve]

Bolero421 is close, but slightly incorrect. With safe sleep, the contents of RAM are stored to the hard drive so that everything, including RAM and the hard drive can be turned off to save power. Previously with sleep, the hard drive was shut down, but RAM ran in a mode where it would maintain its contents, but at a very low power level. Safe sleep saves even more power during sleep. But yes, you should aways wait to see the pulsing light before moving the machine or putting it in a bag.

Steve

[oracle1]

Ok great, that was some good info. Thx

[m_young]

The pulse light on the macbook is misleading, or at least on mine. It comes on when the display goes to sleep, which obviously isn't the same as a full sleep. My iBook only had the light when the whole machine went to sleep.

[Bolero421]

ibook_steve

Yeah, I guess I wasn't really clear on that.

Essentially, when you close the lid on your macbook it prepares for deep sleep / hibernation but actually enters regular sleep (meaning the RAM is still active. If, during regular sleep the power supply is somehow disrupted the contents of the RAM are lost but your session is still saved on the HD allowing for a full, if relatively slow, restoration upon rebooting.

The RAM is kept active for a quick wake-up process, but everything is written to the HD "just in case..."

I think there is a way that involves entering some commands into the console or editing a config file that allows you to put your macbook into hibernate mode (save session to disk and shut everything down, including RAM) instead of regular sleep by closing the lid. Not sure why you'd do this unless you were just really, really low on battery power because the wake-up process from hibernation is much longer than simply using normal sleep (which is pretty much instantaneous).

m_young

I'm not sure but I think that when the indicator light comes on during a display-sleep it remains solid (not pulsing), but I'd have to double check that. In any event, don't move it unless you've shut it down or you've closed the lid and confirmed the light has started pulsing.