Computers tend to freeze up if they’re overburdened. You might think that if you throw enough money at a computer, it should at the very least keep it from freezing but that isn’t how it works. If you run enough resource heavy processes on a system, it will eventually freeze. A system with more capable hardware will obviously be able to take on more processes but it too can be brought to its knees.
When a system freezes, the OS that’s running will try and free up resources and push itself out of its frozen state. That doesn’t always work in which case you have to force shut down the system by holding down the power button. On a Mac, particularly a MacBook, this may not work or perhaps you don’t want to manually force the shut down and then boot up again. If that’s the case, you can automatically restart a frozen Mac by setting it up to do so in advance. Here’s how.
Automatically restart a frozen Mac
In order to automatically restart a frozen Mac, you need to run a Terminal command. This command will require admin rights to run because it will override everything else when it comes down to restarting a frozen system.
Open terminal, and run the following command. You will be prompted to enter the admin password. Once you do so, the system will be set to restart automatically when it freezes.
sudo systemsetup -setrestartfreeze on
Any time you want to disable this, open Terminal again and run the following command. Like before, you will be prompted to enter the admin password in order to execute it. Once it’s been executed, your system will no longer restart automatically if it’s frozen.
sudo systemsetup -setrestartfreeze off
A word of caution
A forced restart or shut down is not the natural shut down state for any system, and Macs are no exception. The above command is basically forcing a restart and it will very likely result in lost data. If you had anything open when your system froze, it is highly likely that some, if not all data that was unsaved will be lost. In this case, apps that have an auto-save feature might also be of little use.
If you have a less capable Mac that tends to freeze often, this is NOT something you want to enable. It’s a useful option if your system tends to run fine normally by freezes up when certain tasks are executed but on a low-resource system, this could just end up crippling it.