How To View And Kill Processes on your Mac

When your Mac slows down or starts behaving erratically, chances are its because an application that’s running, perhaps in the background, is misbehaving. Alternatively, if it’s not an application that’s causing the problem, it will almost certainly be a process associated with the OS or an ancillary service. 

Solving the problem is usually as simple as killing the process, but in order to do that, you need to identify it. Here’s how to view and kill processes on your Mac.

How to kill process using Activity Monitor

  1. Launch Activity Monitor. The easiest way to launch Activity Monitor is to press Command and spacebar to call up Spotlight, then start typing Activity Monitor. When it appears in Spotlight, hot Return to launch it. Alternatively, go to the Utilities folder in the Applications folder and double-click on its icon. Or open Activity Monitor in one click through iStat Menus app.
    Open Activity Monitor from iStat Menus
  2. View and filter tasks. You’ll notice there are five tabs across the top of the Activity Monitor window: CPU; Energy: Memory; Disk; and Network. Clicking on any of those tabs organises processes according to the percentage of that resource they are using. So, clicking on CPU lists tasks in the order of how much CPU capacity they’re using. By default, processes are ordered starting with the one that’s consuming the most of the resource at the top, so you can quickly see where problems are occurring or likely to occur. To flip the order, so that processes consuming the least of the resource are at the top, click the arrow next to Memory, CPU, etc, above the list of processes.
  3. Kill problem processes. When you identify a process that’s causing a problem, either because it’s hogging lots of CPU cycles or memory, or because it’s highlighted in Activity Monitor as having crashed, you need to kill it. To do that, click on the process and click the ‘x’ in the Activity Monitor toolbar. The process will quit and free up the resources it was hogging. If it’s a critical process, it will restart. If it’s an application, it will remain shut down.

Activity Monitor

How to view and kill processes in Terminal

  1. Launch Terminal. Use press Command and spacebar to pull up Spotlight then start typing ‘Terminal’. When the Terminal app appears in Spotlight, tap Return to launch it. Alternatively, navigate to the Utilities folder in Applications and double-click Terminal.
  2. View processes. When Terminal has launched, type ’top’ into the Terminal window. You’ll see a list of currently running processes. At the top of the list is an overview of the processes that are running and the resources they’re consuming.
  3. Kill a process. When you identify a process that’s causing a problem or hogging resources, take note of the number in the PID column next to the name of the process. To kill the process, type ‘kill -9’ followed by the PID number. The problem process will now quit.

How to prevent problems using CleanMyMac

You can prevent problems occurring with apps and processes before you get to the point where you have to kill or quit them. CleanMyMac, available in Setapp, has a number of maintenance routines that, if you use them regularly, will keep you Mac running smoothly.

Here’s how to use it. 

  1. Launch Setapp and search for CleanMyMac.
  2. Open the app and click on Maintenance in the Utilities section in the left hand sidebar. You’ll see a list of tasks that CleanMyMac can perform to optimize your Mac. The first one, Maintenance Scripts, is the first one you should run if your Mac is having problems. 
  3. Run the maintenance scripts. Click on the checkbox next to Maintenance Scripts and then click Run. When it’s finished, click Select Tasks to return to the list of maintenance tasks.
  4. Run other tasks, as necessary.

Remove startup items

One common cause of Macs running slowly or having problems is items that launch automatically at startup. These could be helper apps for something like iTunes, or could be complete apps in their own right. They may be apps you once used but no longer need. 

To review the apps and helpers that startup when you log in

  1. Launch System Preferences from the Apple menu and click on the Users & Groups pane. 
  2. Click the padlock and type in your password. 
  3. Then click your username in the left panel and click the Login Items tab.
  4. Click on any login item that corresponds to an app you no longer use and then click the ‘-‘ button. The app will no longer start up automatically when you log in.

Manage login items in Users & Groups

Reset a problem app

There’s one more thing you can try if an app keeps running slowly or crashing – reset it. Thanks to CleanMyMac, resetting an app is easy. Here’s what to do:

  1. In the left hand sidebar of CleanMyMac, click on Uninstaller, under Utilities. 
  2. Find the app that’s causing problems
  3. Scroll through the list of apps until you find the one that’s been crashing or running slowly. Click on it so it’s highlighted.
  4. Reset the app. With the app highlighted, you’ll see all the files associated with it in the right hand window. Click Application Reset at the top of the window and all the files, except the main application file, will be selected. Click Uninstall. All the selected files will be trashed, effectively resetting the application to its default state. When you launch it the next time, it will behave as if it has just been installed – so you’ll need to recreate any custom settings or preferences.

If resetting the app doesn’t work, the final resort should be to uninstall the app completely and reinstall it. To do that, follow the steps above, but click Complete Uninstallation instead of Application Reset.

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