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iRun26.2
Jan 25, 2011, 05:43 PM
I have the 11.6" MBA and really like the sleep function/instant on. I understand that after about an hour or two in the sleep mode the MBA transitions into a deeper sleep that uses less power.

I would like to know if there is a way to manually force the MBA into the deeper sleep mode immediately so it doesn't spend any time in the higher power initial sleep state. I am fine when it takes a little longer to recover from the deeper sleep (but I do not want to have to reboot my system).

Thanks!

(My assumption is that selecting 'sleep' via the 'power on/off' button does the same thing as closing the lid)



mattydee87
Jan 25, 2011, 06:06 PM
It costs a small fee, but I believe SmartSleep will do what you're looking for and it's available in the App Store

iRun26.2
Jan 25, 2011, 09:19 PM
It costs a small fee, but I believe SmartSleep will do what you're looking for and it's available in the App Store

But now, after going to their web-site, I am convinced that it something I don't want to do because, with so many hibernations (deep sleeps), I will reduce the useable lifetime of my MBA's SSD. I don't want to slow my system down nor weaken the usability of my SSD! (This is my first machine with a SSD and I really can't say I have any idea how a SSD will behave in the long term...but I sure like it in the short-term!) :)

How many hours after you put your MBA to sleep will it hibernate?

KPOM
Jan 25, 2011, 09:58 PM
It goes into deep sleep after about an hour, unless it is plugged in, in which case it won't go into deep sleep. That said, I wouldn't worry about the SSD. I had an SSD in my Rev B that I used for 2 years before I replaced it with the Rev D. It was a slower SSD, to be sure, and I did have some performance degradation, but it was reliable.

iRun26.2
Jan 26, 2011, 08:00 AM
It goes into deep sleep after about an hour, unless it is plugged in, in which case it won't go into deep sleep. That said, I wouldn't worry about the SSD. I had an SSD in my Rev B that I used for 2 years before I replaced it with the Rev D. It was a slower SSD, to be sure, and I did have some performance degradation, but it was reliable.

The deep sleep is also not worth SSD performance degradation (that comes with hibernation) either, in my mind. I no longer want to force deep sleep.

blow45
Jan 26, 2011, 04:52 PM
why would it reduce ssd lifetime?

iRun26.2
Jan 26, 2011, 05:09 PM
why would it reduce ssd lifetime?

A SSD uses Flash memory which can only be read and written to a finite number of times. Plus performance goes down as it gets used. Hibernation writes a huge file to the SSD.

blow45
Jan 26, 2011, 05:21 PM
A SSD uses Flash memory which can only be read and written to a finite number of times. Plus performance goes down as it gets used. Hibernation writes a huge file to the SSD.

that finite number of writes is a non issue by now, by the time you get to that number if you ever do, you 'll be on your third mac. Performance gets down with use unless there's some rubbish collection system, i.e. having cells cleaned up, deleted properly, not just marked deleted, as with trim. I have a hunch apple have so far done none of this as there is no indication a trim like function is there in their flash, but I am sure this will be addressed with lion. In any case with normal use your drive will have to be written and re-written already many times without the hibernation file on the ssd, so it will degrade regardless. As soon as apple implement some garbage collection in the background (and someone correct if by 1/100 chances they already have) this will be a non issue because they performance will not go down when proper trim-like functions are implemented on the flash.

So, to sum up, the finite number times is a non issue, unless you d want to be using this in 15+ (and that's a very modest estimate, it could be 20-30) years, and the performance issue is unavoidable hibernation or not, because with normal use you reach the point where everything has been written on at least once very soon, and after that unless there's trim-like functions within the os, and there aren't any, the problem will be the same if you write 1 or 1000X times on it, because already none of the cells will be virgin, and never written before.

Honey Bee
Feb 4, 2011, 04:41 PM
Hi.
I have just downloaded a widget called "Midnight" free from the apple site. There is a function you can choose to put it into deep sleep.
G.