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I used to use sudo pmset -a hibernatemode 25 to try setting my MacBook to hibernate instead of sleep, so that it pulls power away from the RAM/hard drives, etc. and puts the laptop into a proper sleep. A few major updates ago (maybe El Capitan), pmset ... 25 no longer worked to set my MacBook into hibernate/safe sleep. I'm using a MacBook 13" from 2017. Is hibernate no longer supported on this model?

After hearing about the defect in the 15-inch MacBooks from 2017, I have to admit that I'm concerned they'll find an issue with 13-inch MacBooks as well, and I want to be as safe as possible.

I use a lot of applications whose state needs to be maintained across many days for development and testing, so shutting down my computer every day is not efficient nor is it a viable option.

Here is my pmset -g custom after running sudo pmset -a hibernatemode 25 to try enabling hibernate mode again:

pmset -g custom

Battery Power:
 lidwake              1
 autopoweroff         1
 standbydelayhigh     86400
 autopoweroffdelay    28800
 proximitywake        0
 standby              1
 standbydelaylow      10800
 ttyskeepawake        1
 highstandbythreshold 50
 powernap             0
 gpuswitch            2
 hibernatefile        /var/vm/sleepimage
 hibernatemode        25
 displaysleep         5
 sleep                180
 tcpkeepalive         1
 halfdim              1
 acwake               0
 lessbright           1
 disksleep            10
AC Power:
 lidwake              1
 autopoweroff         1
 standbydelayhigh     86400
 autopoweroffdelay    28800
 proximitywake        1
 standby              1
 standbydelaylow      10800
 ttyskeepawake        1
 hibernatemode        25
 powernap             1
 gpuswitch            2
 hibernatefile        /var/vm/sleepimage
 highstandbythreshold 50
 womp                 1
 displaysleep         10
 networkoversleep     0
 sleep                10
 tcpkeepalive         1
 halfdim              1
 acwake               0
 disksleep            10

pmset -g cap

Capabilities for AC Power:
 displaysleep
 disksleep
 sleep
 womp
 acwake
 lidwake
 halfdim
 gpuswitch
 standby
 standbydelayhigh
 standbydelaylow
 highstandbythreshold
 powernap
 ttyskeepawake
 hibernatemode
 hibernatefile
 autopoweroff
 tcpkeepalive
 autopoweroffdelay
 proximitywake
  • If your computer 'hibernates', it's not able to communicate with any other device, or it's own hard drive for that matter. Hibernation puts the state of your system into the RAM's and 'shut's down'. The only thing that' in real need of power at that point are your RAM's! (RAM memory is volatile so it must be constantly powered to prevent data loss). I suggest you to activate 'Power Nap' in your power setings. When Power Nap is activated, the computer goes into 'Sleep' mode, not 'Hibernation'. Check this info on Apple's website: support.apple.com/en-us/HT204032 – Dakta Moriamé Aug 14 at 16:48
  • Please edit your OQ to include the output of pmset -g custom. – dan Aug 14 at 18:54
  • 1
    SInce you don't have a 15-inch MacBook model mid-2015, you are not concerned by the racall program you referenced. – dan Aug 14 at 18:55
  • @DaktaMoriamé Sleep locks the state of the system into the RAM. Hibernate copies the RAM onto the hard drive in /var/vm/sleepimage and then powers off the RAM. I'll check out Power Nap. – NobleUplift Aug 14 at 19:27
  • @dan Added it! I know that my 13-inch isn't part of the recall program, but the recall program still has me spooked with how I use my MacBook. – NobleUplift Aug 14 at 19:29
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I'd say "Nothing". Assuming there is an defective battery, you can't 'manage' its safety with any specific behaviour. It could fail and overheat while in use, or while charging.

The odd recall notwithstanding, Apple has worked very hard at making laptops use minimal power when closed, while also allowing some necessary background tasks; and then letting them spring back to life when you open the lid.

Modern SSDs use a fraction of the power of the old mechanical hard drives that needed to be spun down to save energy.

I rarely turn off my 2014 MacBook Pro, and only reboot it when updating the OS or troubleshooting.

  • There's no such thing as 0 risk, you're definitely right. Thanks for putting me more at ease! – NobleUplift Aug 14 at 19:33
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Your setting of hybernate mode is the one to achieve exactly what you described.

But you are correct. I use this setting since many years and through many versions of MacOS (Yosemite, El Capitan, Sierra & High Sierra). From memory I reported many times the same problem to Apple about this mode failing on output of hibernation when the battery was nearly empty.

I guess there is a problem about correctly evaluating the power required to make the /var/vm/sleepimage dump of the virtual memory. Since they never answered me, I guess they never fully understood the problem.

Now I know for sure that the function lidwake is failing.

Is hibernate no longer supported on this model?

No it is.

But since a negative question is leading to confusing answers here is a clearer one.

The command to check directly the availability of this function is:

pmset -g cap

and look for the key function: hybernatemode

  • I'll try sleeping my computer for more than 5 minutes with no power to see if it comes out of hibernation or sleep mode. – NobleUplift Aug 14 at 19:33
  • To shorten your testing cycle I suggest you: pmset autopoweroffdelay 1. Don't forget to reset to its default value afterward. – dan Aug 14 at 20:03

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