Mac OS X is generally well-behaved when it comes time to turn off your computer. Apple wants responsiveness, so most Macs will shut down in seconds, particularly if solid state storage is equipped. In rare instances the proper OS X kill processes go wrong, greatly increasing shutdown times. Here are a few potential fixes.
Turn Off “Reopen Windows When Logging Back In”
By default a Mac will save your currently active session into memory when it shuts down, which lets you resume exactly where you left off when you turned your computer off. Transferring the information to memory can take time, however, so you may increase shut down speeds by turning this feature off.
Doing so is easy. Your Mac will prompt your with an “are you sure you want to shut down” – or restart, as the case may be – message which includes a “Reopen windows when logging back in” checkbox. Un-check it. Note that you may need to perform a few restart cycles to see benefits.
Decrease The Time OS X Takes To Exit Programs
A lot of problems with slow shut down are caused by a familiar issue that plagues virtually every platform; hung software. Programs are supposed to shut down when the operating system requests it, but sometimes they don’t comply. That, in turn, causes a delay or may even prevent a proper shut down entirely.
Mac OS X combats this with a 20-second shutdown timer, after which the system force-kills open programs. Still, 20 seconds can feel like a long time, and you can decrease the time OS X provides programs.
There are two ways to do this. One is via sudo commands. Open the Terminal window and then enter the following commands exactly as shown (copy and paste).
sudo defaults write /System/Library/LaunchDaemons/c\ om.apple.coreservices.appleevents ExitTimeOut -int 5
sudo defaults write /System/Library/LaunchDaemons/co\ m.apple.securityd ExitTimeOut -int 5
sudo defaults write /System/Library/LaunchDaemons/c\ om.apple.mDNSResponder ExitTimeOut -int 5
sudo defaults write /System/Library/LaunchDaemons/c\ om.apple.diskarbitrationd ExitTimeOut -int 5
sudo defaults write /System/Library/LaunchAgents/com.apple.\ coreservices.appleid.authentication ExitTimeOut -int 5
You’ll have to provide your admin password when you enter the first command. After that, you can enter the rest unhindered unless you close and the re-open Terminal.
As you might have guessed, these commands change the timer to 5, but you could use any other number you desire.
An alternative way to accomplish this is with an app management program like Ctrl Alt Delete [No Longer Available] or App Killer. These don’t automatically close programs at shutdown, but they let you close any slow pokes manually. Also, you can use these utilities to discover the culprits and then take further action, like uninstalling, updating or troubleshooting the troublesome software.
Free Up Some Disk Space
This is a simple tip, but it must be mentioned. Virtually all computers start to run into problems when they’re very low on disk space because some of said space is used to store temporary data. This can in turn cause shut down problems, particularly if you have open applications that are trying to save their state during the shut down process. If you have less than 20% of your disk free, try cleaning out your drive and see if that makes a difference.
Check Your Disk Permissions And Health
Another possible reason for poor hard drive performance is an issue with disk permissions on the file system itself. Though uncommon, these issues can arise due to software that installs and uninstalls itself improperly or because of user error.
You’ll need to open Disk Utility (under Applications > Utilities) to check permissions. Once there, select your system drive (the one on which OS X is installed) and run Verify Disk Permissions and Verify Disk. If a problem is found with either, follow up by hitting Repair Disk Permissions and Repair Disk.
Rebuild The Kernel Extension Cache
Some users have reported a problem with the OS X root directory losing proper ownership permissions. The cause of this isn’t clear, but it can increase shut down and boot times. To fix the issue open Terminal and use the following commands.
sudo chown root:admin /
sudo kextcache -system-prelinked-kernel
sudo kextcache -system-caches
Each command should be entered separately, and you’ll be prompted for your admin password when you enter the first. Rebuilding your kernel extension cache in this way should solve any problems related to a root directly with improper permissions.
Reset PRAM and SMC
Macs two special traits known as Parameter Random Access Memory (PRAM, or NVRAM on Intel systems) and System Management Controller (SMC) that handle certain core system functions, like the backlighting brightness and speaker volume. Some users have linked problems with PRAM or SMC with slow shut down and boot performance.
To reset PRAM you need to turn off your Mac and then turn it back on. Immediately hold the Command, Option, P and R keys simultaneously (you must do this before the gray boot screen appears). Continue holding these keys until you hear a second startup sound, then release. Note that performing this activity will reset certain information, such as your time zone.
You can also reset SMC, but doing so is more complicated and the steps can depend on the Mac you have. Fortunately, Apple has a guide to resetting SMC that will help you determine the measures you need to take on your particular Mac.
These tips should decrease your boot times, but if you still need help try asking on MakeUseOf Answers. Your fellow readers may be able to suggest solutions applicable to your specific plight.