Warning message from disabling hibernation

[neurophysicist]

Hello,

I replaced the HDD in my early 2011 2.2 i7 MBP with a Samsung 840 Series 500GB SSD.

I was reading about SSD optimizations online and many places recommended turning off hibernation:

http://sysadmin.flakshack.com/post/9...-os-x?ad22ade0
http://blog.alutam.com/2012/04/01/op...d/#hibernation

I disabled it in the terminal, but this message was also returned. I wasn't really sure what it meant, so I was hoping someone here does. Thanks.

**-MacBook-Pro:~ **$ sudo pmset -a hibernatemode 0
Warning: Idle sleep timings for "Battery Power" may not behave as expected.
- Disk sleep should be non-zero whenever system sleep is non-zero.
Warning: Idle sleep timings for "AC Power" may not behave as expected.
- Disk sleep should be non-zero whenever system sleep is non-zero.
**-MacBook-Pro:~ **$ sudo pmset -g
Active Profiles:
Battery Power -1
AC Power -1*
Currently in use:
standbydelay 4200
standby 0
womp 1
halfdim 1
hibernatefile /var/vm/sleepimage
gpuswitch 2
sms 1
networkoversleep 0
disksleep 0
sleep 10
hibernatemode 0
ttyskeepawake 1
displaysleep 10
acwake 0
lidwake 1

Anyone have ideas? No really sure what is meant by "Idle sleep timings may not behave as expected." Does this mean problems may come about, or is it nothing to worry about? And if so, why the warning?

My second question is sometimes terminal says "(sleep prevented by )" followed by a PID. Sometimes this is time machine, but other times it is blank (as seen in the image attached).

Last, I noticed that the SMS sometimes is switched back on to "1", even though I set it to off. I was wondering if this happens to other people as well—do the settings change when turning the computer back on?

Thanks.

 

[trigonometry]

Could be totally wrong but...

I disabled hibernate and I think I remember getting the same message. Basically, you have two contradictory sleep settings. Shouldn't be a problem though.

To address your second question, I really don't know the answer but I would suggest bringing up activity monitor to narrow down the culprit whenever it happens. Or bring up force quit, option-cmd-power button.

Last, some changes in terminal don't stick. You have to enable them after every restart.

 

[neurophysicist]

Could be totally wrong but...

I disabled hibernate and I think I remember getting the same message. Basically, you have two contradictory sleep settings. Shouldn't be a problem though.

To address your second question, I really don't know the answer but I would suggest bringing up activity monitor to narrow down the culprit whenever it happens. Or bring up force quit, option-cmd-power button.

Last, some changes in terminal don't stick. You have to enable them after every restart.

Thanks trigonometry. Is the only disadvantage to disabling hibernation then that if you completely lose battery it's basically like rebooting?

I googled around and found this manual:

http://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/pmset.1.html

it says:

disksleep - disk spindown timer; replaces 'spindown' argument in 10.4 (value in minutes, or 0 to dis-
able)

and the original message said "disk sleep should be non-zero when system sleep is non-zero." Does it have anything to do with leaving the "put hard disks to sleep when possible" setting unchecked? Thanks again!

 

[jenzjen]

I uncheck the hard drive sleep setting box but also set the machine to sleep "never" in the energy saver panel - I think it is the latter that when changed make the error you see go away when you rerun disabling the hibernation command.

 

[neurophysicist]

I uncheck the hard drive sleep setting box but also set the machine to sleep "never" in the energy saver panel - I think it is the latter that when changed make the error you see go away when you rerun disabling the hibernation command.

Thanks jenzjen. How come you set your sleep to never? Does it wear the SSD that much? I figured I would just go with hibernation disabled but I'm curious if other SSD users disable sleep completely, and the benefits/drawbacks.

 

[dastinger]

Do users with an originally equipped SSD MBP "need" to do this? Or is it already pre programmed?

 

[Weaselboy]

Do users with an originally equipped SSD MBP "need" to do this? Or is it already pre programmed?

Nobody really needs to do it unless you are just absolutely desperate for that last little bit of SSD space that is used by the hibernation image. Unless you are running your battery until it dies all the time, hibernation has no impact on SSD write cycles.

A default OS X install has hibernation turned on.

 

[1member1]

Hibernate mode is a good thing and with SSD this works much better so why even disable it ?

 

[trigonometry]

Nobody really needs to do it unless you are just absolutely desperate for that last little bit of SSD space that is used by the hibernation image. Unless you are running your battery until it dies all the time, hibernation has no impact on SSD write cycles.

A default OS X install has hibernation turned on.

I kind of agree but I have heard of people freeing up gigabytes+ which is not insignificant when you have a 128GB SSD.

 

[Weaselboy]

I kind of agree but I have heard of people freeing up gigabytes+ which is not insignificant when you have a 128GB SSD.

The image would be the same size as the system's RAM. So if your Mac portable has say 16GB RAM, the hibernation image would be 16GB. So yeah, if you are really tight for space it could help.

 

[dastinger]

I almost never run out of battery in a way that I could need hibernation.. and, I have 16GB of RAM so that would make a difference. If, on any time, I'm running out of space, I'll do it.

Thanks a lot for the explanation, Weaselboy