Powerbook G4 (Double-Layer SD) "Safe Sleep"

[MacBytes]

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Category: Apple Services
Link: Powerbook G4 (Double-Layer SD) "Safe Sleep" (http://www.macbytes.com/link.php?sid=20051024010612)

Posted on MacBytes.com (http://www.macbytes.com)
Approved by Mudbug

[mkjellman]

very very cool..instant hibernation otherwise

[nagromme]

I like that it doesn't ALWAYS save the sleep state to HD, only in the event of total power failure.

And it's not some option you must enable or disable. It just does it if it needs to.

Despite the lack of faster Freescale chips, it's nice to see some little additions like this, because the NEXT generation is bound to share them.

[Nermal]

Yes, it's good in a way - the lack of faster chips is forcing innovations in other areas :)

[crenz]

I like that it doesn't ALWAYS save the sleep state to HD, only in the event of total power failure

That would have been nice, but the article says:

Prior to your system entering sleep, Safe Sleep automatically saves the contents of main memory

I fear it might now take a long time to enter sleep mode, especially with notebooks with a lot of RAM.

[killmoms]

I fear it might now take a long time to enter sleep mode, especially with notebooks with a lot of RAM.
Hmmm... good point. Maybe there's a way to keep it from doing that unless the battery's below a certain level when it's put to sleep, say 5 - 10% or something? I wouldn't think this feature would engage if your battery was at 75% or something, since it's pretty damn unlikely that it's going to drain the battery in sleep mode then.

[nagromme]

That would have been nice, but the article says:

Ah, I passed over that. Too bad. That IS a question, then.

I guess waking/"half-waking" to do it "as needed" would be a problem: it would mean HD activity without warning at a moment when you think your computer is dormant, and might by manhandling it in ways you wouldn't be if it were powered on knowingly.

Hopefully they wouldn't have done it if it make sleep times lengthy. Writing 1 GB of data to disk sounds like something you couldn't allow to be typical on shutting the lid.

One thing that might help with the speed of the process: much of what's in RAM is ALREADY stored on disk in virtual memory. Maybe it's just a matter of saving a small amount of data, and preparing to USE it all in a new way upon restart after a power failure.

I would think even desktops could benefit from that in fact.

[sjk]

Safe Sleep would be a useful feature for semi-portable minis and iMacs, too.

[zapp]

That would have been nice, but the article says:



I fear it might now take a long time to enter sleep mode, especially with notebooks with a lot of RAM.

Just got a new 15" powerbook today. it sleeps when you close the lid and wakes upon opening it. Close the lid pull the battery it stays sleeping. The only difference is when you shut the lid it doesn't start snoring(light changing its brightness) right away, I hear the disc spinning then it snores. But when you open the lid it is immediatley on. I have 2gb of ram installed. Then only problem I had is it didn't recognize the crucial ram I bought in the upper slot, when I switched them it was fine and saw both chips. I did a BTO with 1Gb in one slot and the 7200 rpm drive.

[nagromme]

Note that older PowerBooks can stay asleep with the battery removed, too. That's a different feature: a permanent second battery installed inside every PowerBook. It's small--just enough power to maintain sleep for a short while and allow swapping main batteries without shutting down.

This new feature means that even if BOTH batteries ran dead, you could still "wake from sleep" with your work intact once you restored some power source.

Good to hear that sleep is still pretty quick. My old PB doesn't snore quite instantly either. That's OK--waking fast is more important, and this new feature doesn't affect that.

[wordmunger]

That's one thing I like about Apple: most of the time, features like this are implemented exactly as they should be. With this feature, there's no trade-off. Sleeping and waking are just as fast as they used to be, but now if your battery dies while sleeping, you're protected.

[Sharewaredemon]

Note that older PowerBooks can stay asleep with the battery removed, too. That's a different feature: a permanent second battery installed inside every PowerBook. It's small--just enough power to maintain sleep for a short while and allow swapping main batteries without shutting down.

This new feature means that even if BOTH batteries ran dead, you could still "wake from sleep" with your work intact once you restored some power source.

Good to hear that sleep is still pretty quick. My old PB doesn't snore quite instantly either. That's OK--waking fast is more important, and this new feature doesn't affect that.

I like that feature, I didn't really figure it out until I was reading through the posts.

You see I was trying to calibrate the battery for a powerbook at work, and for whatever reason I took the battery out and it stayed on... Kinda creeped me out.

Now I realise how cool that is.

Being able to swap batteries on a flight without shutting down must be a godsend for people.

[nagromme]

I assume that all laptops have that extra battery inside, not just Apple's. True? Can you swap batteries on a Windows laptop just by shutting the lid?

[sjk]

Can you swap batteries on a Windows laptop just by shutting the lid?Not without hibernating (which can be configured to happen when closing the cover) on my on my 5-year-old Toshiba.

Anyone use Safe Sleep when it was added with Power Manager 2.0 on Macs back in 1999 (according to an old Apple technote)? Surprising it took this long to reintroduce that feature with OS X and new hardware.

Oh, is it possible to keep the new PBs configured to use "normal" sleep when the cover's closed but still put them into Safe Sleep, say, from the Apple menu? Or is it just one or the other when the cover is closed?