Your system has run out of application memory? Here’s a fix

macOS is based on Unix, which means that its memory management is pretty robust. However, it’s not perfect, and so you may still see an error message telling you that “Your system has run out of application memory.” What does it mean, and why does it happen? We’ll explain what causes the error and what to do to fix it.

What does “your system has run out of application memory” mean?

macOS stores data used for active processes in RAM. If space in RAM runs low, macOS starts storing data on your main boot drive and swapping it between there and RAM as it needs it. This is known as virtual memory. For this reason, you should always have a decent chunk of free space on your boot drive — 10% is a good rule of thumb. If you don’t have enough space on your boot drive for an application to store temporary files, you will see the error message telling you your system has run out of application memory.

Why does it happen?

There are a number of things that can cause this error message to appear, although, as we said, macOS’ memory management is very good, so if you do see the message, you should take action.

Reasons include:

  • Running low on disk space on your boot drive
  • Having lots of apps open simultaneously
  • Having lots of browser tabs open
  • An application “hogging” memory

The best way to avoid seeing the error message is to make sure you keep as much disk space as possible free on your boot drive. The easiest way to do that is to run CleanMyMac X’s System Junk module regularly. This handy tool makes it easy to identify and remove all kinds of junk files. These include temporary files that should have been deleted but weren’t cache files and old logs. You can quickly free up several gigabytes of space with just a few clicks.

How to fix the “Your system has run out of application memory” error

There are other ways you can tackle the problem, too.

1. Restart your Mac

This is the first thing you should try. Restarting your Mac clears the cache and other temporary files and gives back disk space used as virtual memory.

2. Update macOS

Whenever you run into problems on your Mac, it’s a good idea to check if there is an update available, in case the problem is a bug and there is a fix for it in the update.

  1. Click on the Apple menu and choose About this Mac.
  2. Choose Software Update.
  3. If there is an update available, follow the instructions on-screen to install it.

3. Use Apple’s Storage Management

Apple provides some useful tools to help you manage space on your boot drive.

Apple's Optimized storage tool
  1. Click the Apple menu and select About this Mac.
  2. Choose the Storage tab.
  3. Press Manage.
  4. Select Recommendations, and you will see a list of things Apple recommends you do to free up storage space. Decide which recommendations you want to take and follow the instructions.

4. Update apps

As with macOS, it could be that one or more of the applications you’re running has a bug that causes it to hog memory. You should check whether there are updates available for those apps. For apps downloaded from the App Store, you can do that on the Store. For other apps, click the app’s name on the top-left corner of your screen (there should be a “Check for Update” option).

Tip

CleanMyMac X has an updater module that can update multiple apps simultaneously and is quicker than updating apps manually. It also has an Uninstaller module for removing apps that you no longer use and getting rid of all the files associated with them.

5. Close apps you’re not using

Keeping apps running in the background when you’re not using them uses up a lot of virtual memory. It’s good practice to quit apps when you stop using them. Press Option-Command-Esc to open the Force Quit menu. If there are programs you’re not currently using, quit them.

6. Close browser tabs

Modern web browsers can have so many tabs open simultaneously that many of us spend all day with dozens of them open. And then we wonder why our Macs are running slowly. Keeping tabs open means they update in the background, taking up memory and other system resources. Bookmark tabs you use regularly and then close them when you’re finished using them.

How to check the memory on your Mac using Activity Monitor

If you’ve completed all the steps above and are still getting the same error message, you’ll need to do some detective work to track down the source of the problem. macOS has a great tool for this work – Activity Monitor. It allows you to see all processes currently running on your Mac and list them according to the system resources they are consuming, including RAM. In this way, you can see which processes are hogging memory and possibly causing the error message, then quit them.

Mac Activity monitor
  1. Go to Applications > Utilities and launch Activity monitor.
  2. Click the Memory tab to see a list of processes, including applications and browser tabs, that consume memory.
  3. Select a process or app, and click the “X” sign to close it.

7. Review browser extensions

Obsolete or buggy browser extensions could be another cause of memory problems on your Mac that could lead to the same error message. Take a look at the extensions in each of the web browsers you use and decide whether you use them or whether they can be disabled or removed.

In Safari, you’ll find extensions in Preferences > Extensions. In Chrome, you can access them by typing chrome://extensions in the address bar.

8. Uninstall applications

Some applications take up several gigabytes of space on your Mac, so if you don’t use them, it makes sense to uninstall them. If they were downloaded from the App Store, you could always download them again when you need them. Or, if not, you should be able to re-download them from the developer’s website. Did you know, for example, that Microsoft Word takes up to 2GB of space?

9. Install more RAM

The last resort, and the most expensive option, is to install more RAM in your Mac if you can. Having more physical RAM will mean macOS needs to use your boot drive less often to store swap files. However, not all Macs can have RAM upgraded after purchase, and for those that do, it usually means a trip to an Apple Store or an authorized service center.

There are many reasons you might see an error message telling you that your system has run out of application memory. But they all point to the same thing — a shortage of space on your boot drive. So, the simplest solution is to free up more space. However, you should follow the steps above to identify whether there is a problematic app taking up more memory than it should.

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