Active2 years, 11 months ago
In standby mode, the RAM is powered off. On these machines it only takes a few extra seconds to come out of hibernate compared to coming out of sleep. You can also run pmset -g to see whether standby is set and how long standbydelay is. If you don't see standby, your hardware doesn't support this feature.
On Windows, you can hibernate your computer, so that it starts a lot faster while consuming zero energy while 'hibernating'.
I see an option to Sleep on my Mac mini but not hibernate. Does Mac support hibernation?
I am on Leopard.
- Pmset is a command line utility to manipulate power management settings in Mac OS X. They provide greater flexibility and access to several options not available in the GUI interface. They provide greater flexibility and access to several options not available in the GUI interface.
- Disable Automatic GPU Switching. You may want to consider looking into the Terminal command pmset. You can read its manual page by typing man pmset in the Terminal app. It uses the same files as System Preferences to configure power related settings but offers more options and granularity along with various useful logging features/stats.
- Pmset is a command line utility that is used to manipulate the power management settings in Mac OS X. With this command, users can change a multitude of settings relating to their Mac’s response to certain power-related conditions, as well as troubleshoot power-related issues. This article will highlight a few of the more useful pmset commands.
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8 Answers
OS X only has only one 'sleep' option. You cannot change its name, but to change its behaviour, I use an old version of SmartSleep on a Mac mini (though in the MacBook-like 'sleep & hibernate' mode). It works for a mini, though the website only refers to MacBooks.
(SmartSleep was still free when I wrote this in 2009.)
I occasionally get complains about hardware not having been removed properly (but OS X never tells me what hardware, and my Time Machine USB disks seem fine — I should peek into the logs one day, and I assume this is related to OS X, not to SmartSleep).
I've quickly tested SmartSleep's 'hibernate only' on that mini (Intel; running 10.5), and it seems to work as well. Doing these tests, I noticed that after the display goes black the power light starts pulsing (like to indicate sleep rather than hibernate) for a few seconds. Maybe it's still writing RAM to disk then. (Until now, I always thought that on my MacBook the pulsing indicated that all was done. But now I think that, whichever sleep mode one is using, one should probably not unplug the power too soon). After a short while, it powers down completely.
In 2006, Macworld explains how to achieve the same without that SmartSleep preference pane. To check the current setup:
According to Macworld's old article the following applies, but be sure to read Lauri's answer that suggests that nowadays only 0, 3 and 25 should be used instead:
- 0 — Old style sleep mode, with RAM powered on while sleeping, safe sleep disabled, and super-fast wake.
- 1 — Hibernation mode, with RAM contents written to disk, system totally shut down while “sleeping,” and slower wake up, due to reading the contents of RAM off the hard drive.
- 3 — The default mode on machines introduced since about fall 2005. RAM is powered on while sleeping, but RAM contents are also written to disk before sleeping. In the event of total power loss, the system enters hibernation mode automatically.
- 5 — This is the same as mode 1, but it’s for those using secure virtual memory (in System Preferences » Security).
- 7 — This is the same as mode 3, but it’s for those using secure virtual memory.
And the same numbers can be used to change the sleep mode setting:
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ArjanArjan27.4k1111 gold badges6666 silver badges107107 bronze badges
I wrote a script that will let you enter hibernation immediately (without changing your settings permanently). I find it quite useful, as I like the default settings, but want to forcibly enter hibernation when on the road. Maybe someone else will find it useful too ;-)
oligofrenoligofren
The pmset man page also recommends using
25
instead of 1
.0000 1000 (bit 3) encourages the dynamic pager to page out inactive pages prior to hibernation, for a smaller memory footprint.
0001 0000 (bit 4) encourages the dynamic pager to page out more aggressively prior to hibernation, for a smaller memory footprint.
We do not recommend modifying hibernation settings. Any changes you make are not supported. If you choose to do so anyway, we recommend using one of these three set- tings. For your sake and mine, please don't use anything other 0, 3, or 25.
[..]
hibernatemode = 25 (binary 0001 1001) is only settable via pmset. The system will store a copy of memory to persistent storage (the disk), and will remove power to memory. The system will restore from disk image. If you want 'hibernation' - slower sleeps, slower wakes, and better battery life, you should use this setting.
Some laptops now enter hibernation (standby mode) after about an hour of normal sleep if:
- Power Nap is not enabled (so not by default)
- The computer is on battery power
- The computer is not connected to USB devices or external displays and not paired with Bluetooth devices
Laptops, Mac minis and iMacs use about 0.2-0.4 W when off or hibernating and 0.8-1.4 W in sleep mode. Hibernation (and the hibernation + sleep mode that laptops use by default) might also reduce the lifespan of drives.
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LriLri32.5k55 gold badges9595 silver badges135135 bronze badges
And for OS X Lion this works better for Hibernation
sudo pmset -a hibernationmode 25
than
sudo pmset -a hibernationmode 1
as hibernationmode 1 can cause crashes for some reason.
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For answers which rely on twiddling the 'hibernatemode' via pmset, it's useful to note that the 'force' option on pmset makes the changes transient. The setting won't be remembered when the system wakes up from hibernation. For example:
Will change the hibernate mode to represent a traditional hibernate (i.e. system state written to disk and power removed) but only until the next time the system is powered on or the settings are read from disk (
pmset touch
).Using the force option avoids the need to save and restore current hibernatemode settings.
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user210274user210274
yup. it's called safe sleep. easiest way to get it is to use the deep sleep widget.
yanokwayanokwa
Hibernation will also be triggered automatically if your laptop battery runs down completely.
Bob DBob D
I have read that 'Safe Sleep' is on by default on all Intel Macs and some late model PowerPC machines (I think the Intel mini's have this support, but the PPC ones probably do not—without unsupported hacks).
Mac Pmset Manual Download
But 'Safe Sleep' by itself is not exactly the same as 'hibernation'. It is a combination of saving RAM to disk but also doing a normal sleep. This allows for a fast wake, and also preserves the system state if the power happens to fail completely while the machine is sleeping.
You can tell if a system is using Safe Sleep by (after at least one sleep) checking for a file /var/vm/sleepimage that is the same size as the installed RAM. Also when Safe Sleep is active there will be a longer delay between clicking the Sleep menu item (or button, or holding Command-Option-Eject) before the machine's status light starts its normal fade-up/fade-down loop.
The final bit of the solution is to get the machine to fully power off after saving RAM the sleepimage. It seems like it is possible to configure this using the command-line program pmset to set the hibernatemode. You might checkout something like Deep Sleep for an automated way of making this configuration change.
Chris JohnsenChris Johnsen30k44 gold badges8686 silver badges9696 bronze badges
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pmset
is a command line utility that is used to manipulate the power management settings in Mac OS X. With this command, users can change a multitude of settings relating to their Mac’s response to certain power-related conditions, as well as troubleshoot power-related issues. This article will highlight a few of the more useful pmset
commands. For commands that have a zero at the end, simply replace the 0 with a 1 and re-execute the command to restore default behavior.Set Your Portable Mac to Stay Asleep When the Lid is Opened
By default, Mac laptops will wake up if a sleeping machine’s lid is opened. You can prevent this behavior and choose to wake the Mac on your own terms by entering the following terminal command:
Conversely, add the following flag to prevent the Mac from going to sleep when the lid is closed:
Prevent Your Mac from Sleeping When the Power Button is Pressed
Have a Choice When Your Mac’s Power Button is PressedPressing a Mac’s power button once will, by default, put the Mac to sleep (for Lion laptops, it brings up the power options menu). You can prevent this behavior with the following terminal command:
Prevent Your Portable Mac from Waking When the Power Source Changes
For Mac laptops, plugging or unplugging an AC Adapter can wake the computer. You can prevent this with the following terminal command:
Prevent Your Mac from Sleeping Due to Idleness
To keep your Mac awake even if you leave the computer idle, use the following command:
With this command running in the Terminal, the Mac will never fall asleep no matter how long the machine is left idle. Once you’re ready to change back to default behavior, press Ctrl-C.
Troubleshoot Sleep Issues
If your Mac isn’t sleeping like it should, you can run the following command to get information about all your power settings and track down the culprit that’s preventing your Mac from getting its beauty rest:
Track Down What’s Preventing Your Mac from Sleeping
This command will display in the Terminal window all the pmset arguments currently in use and their value. It’s helpful to have a guide to decipher these arguments and their value indicators, so check out Apple’s Manual Page for
pmset
.In this case it’s showing process ID 173 as keeping the Mac from sleeping. Using the ps command as:
This shows us that coreaudiod is the culprit. In this instance, iTunes was playing a song. Stopping playback released this “imposition” and the computer was back to being allowed to sleep.