MAC OS power Management Big analysis

Sleep mode-hibernatemode-is the way the Mac works under sleep mode, there are currently 3 main types.

Hibernatemode 0: Memory remains powered while sleeping, other components are powered off, and memory data is not written to the hard drive. The advantage is that you can quickly wake up and sleep fast, because memory keeps powering up, whether it's waking up or going to sleep is 1 seconds, saving SSD space and life, because the memory data is not written to the hard disk, so there is no memory image on the hard disk, and does not shorten the SSD life. However, if the battery is not in the process of sleep, the Mac will lose all the memory data, the data security is not very high.

Hibernatemode 1: Memory data is written to the hard disk during sleep, all parts of the computer are powered down when the write is completed, and the memory image is read from the hard disk when it wakes. The advantage is power-saving, the same as electricity, because all parts have stopped working, also not afraid of the battery will lose memory data. But the disadvantage is also obvious, the need to enter sleep and wake up time, for mechanical hard disk mac especially obvious, usually to turn chrysanthemum more than 10 laps. For SSDs, the Mac consumes hard disk space because it has a memory image that is the same size as memory, which also shortens SSD life.

Hibernatemode 3: A combination of 0 and 1, when sleep memory data is written to the hard disk while maintaining memory power. This mode, also called safe Sleep, is the default sleep mode for Mac.

Change Hibernatemode mode: Open "Terminal", enter: sudo pmset-a hibernatemode 0

In terminal input:pmset-g Custom This command can display all the power settings of the system (see the Apple Developer documentation for more details):

Battery Power is the power setting when using the battery, AC power is the power setting when the external power supply.

Lidwake: When the screen is lifted, the wake-up mac,1 is turned on 0 is off
Autopoweroff: If the Mac is asleep after a specified amount of time, the memory data is automatically written to the hard disk, and the power of all parts is switched off, and 1 is turned on 0 is off. But LZ found that even in the open state, this function does not work, you can ignore it, you can also turn off
Autopoweroffdelay: The time when the Autopoweroff function is enabled, that is, the "specified time" as stated above, in seconds
Standby: The function is the same as Autopoweroff, but only when the Hibernatemode is 3, 1 is open 0 is off. But LZ has not been able to understand what Autopoweroff and standby have different, supposedly it should be different
Standbydelay: The time of the standby feature is enabled, the unit is the second
ttyskeepawake: The remote user is active while preventing the Mac from going to sleep, 1 is turned on 0 is off
hibernatemode: sleep mode
Darkwakes: This is Power Nap, you can choose to open or close in System Preferences, as set here is the same, 1 is open 0 is off
hibernatefile: memory Image storage address, this can also be changed, but the path must be root path
displaysleep:The MAC is idle for a long time to enter the monitor sleep, 2013 Air System Preferences have no such option, Pro is some, but in fact you can change through Pmset. Unit is the minute, this time cannot be longer than the time set under Sleep
Sleep :How long the MAC is idle and then goes to sleep, which is also in the system preferences, in minutes
acwake: wake-up when power is changed, that is, when plugged in or unplugged from an external power supply mac,1 is on 0 is off
Halfdim: When the monitor sleeps, the display brightness changes to half of the current brightness, and 1 is turned on 0 is off. If this function is turned off, the monitor will sleep directly off the monitor.
lessbright: When using the battery to make the display brightness darker, system preferences also has this, 1 is open 0 is off
disksleep:How long the MAC is idle and then shuts down the hard drive. This system preference also has, just changed a word-if possible, put the hard drive into sleep-the system will automatically according to sleep time to set a suitable time. Unit is seconds, this time can not be longer than the time set under Sleep
Sleepservice:LZ has not figured out what this is for, please know the Feng Friend explained.
womp: network remote wake-up, 1 is on 0 is off
networksleep: This setting affects how your Mac provides network sharing services during sleep

It's also easy to change a setting by opening the terminal and entering the command in the following format:
sudo pmset-# $ &
Where the # number has 4 parameters, namely: C B u A, the role is to indicate that this command modifies which power settings under the parameters. C for external Power, b for battery, u for UPS, a for all power.
$ is a specific parameter, such as you want to modify the sleep mode, that is hibernatemode; modify sleep idle time, it is sleep.
& is the value of the parameter
For example, if you want to modify an external power supply that is a MAC monitor sleep idle time is 10 minutes, then enter:
sudo pmset-c displaysleep 10

Want to repair change the hard drive under all the power supplies sleep idle time is 15 minutes, that is:
sudo pmset-a disksleep 15

MAC OS power Management Big analysis