What do I do when my Mac is out of application memory
If you've ever seen a message on your Mac saying “Your system run out of application memory," you might wonder what’s going on, especially if you haven’t opened that many apps. The culprit is often something called a memory leak. But what does that mean, what is wrong, and how can you fix it?
The short answer if you don’t have time to read the entire article: Just restart your Mac. This was likely a temporary glitch and not a sign that you need to upgrade your computer. But you should check for software updates while you’re restarting anyway.
Here is a photo a client sent me recently. For some reason, his Mail app was using 50 GB of memory. That’s over 50,000 (!) megabytes. We’re not sure of the specific cause, but a restart solved his problem and it didn’t come back.
Understanding memory and RAM
Your Mac has RAM (random access memory)—this is the short-term memory your computer uses to run apps and perform tasks. Think of it like a workbench: the bigger the workbench (RAM), the more tools (apps) you can spread out while working.
Be careful not to confuse memory with storage. Storage is what stays on your computer when it gets turned off, like your documents and your apps. For more details on the difference, read my blog post about that.
What is a memory leak?
A memory leak happens when an app takes up space on your workbench but forgets to put its tools away when it’s done. This is due to a bug in the app or some other sort of malfunction. Over time, your workbench gets more and more cluttered, even if you’re not actively using those tools. Eventually, there’s no room left to do anything else. That’s when your Mac runs out of application memory, and you start to work less efficiently or not at all, just like trying to work on a cluttered bench.
Why restarting your Mac helps
Restarting your Mac clears everything off the workbench, including tools left out by apps with memory leaks. This gives you a fresh, clean space to work with and helps your system run smoothly again.
Fixing memory leaks
Every app has bugs. Apps are huge with millions of lines of code, so there is no way to get every line 100 percent perfect. That’s why there are software updates seemingly continuously. Most of the time, simply restarting your computer gets rid of the memory leak because it’s usually just a one-time glitch. But if it keeps happening, there are a few things you can try:
Keep macOS and your apps up to date – Updates often include fixes for memory issues. Update your Mac system software. And look for any updates for the app that is having the memory leak. The two interact, so it is impossible to know which one is the culprit. If the app uses any plugins or extensions, look at updating those or removing any that are no longer used.
Restart your Mac regularly – No matter how well the software on your computer is written, memory leaks will happen. Most people find that they have to restart every 1 to 4 weeks to keep things running smoothly.
Clean up old extensions and launch agents – this is something you may want to consult with someone like me on, but you can disable startup items on your Mac in System Settings > General > Login Items & Extensions. None of these are required for your Mac to operate, but some may be needed for third-party apps. If you have some really old items in here, they can cause problems. If something doesn’t work after disabling one, go back here to turn it back on. I don’t recommend just going through and turning off everything or anything you don’t recognize, but if there is an app you know you are no longer using it’s probably safe to disable it here. Someone who knows their way around Mac may be able to more fully and safely remove it.
Check for malware – though increasingly uncommon on Mac in recent years because of security measures Apple has taken with their modern software, malware occasionally makes its way through. On top of the security and privacy concerns of malware, it’s often terribly written and messes with an otherwise fine computer. I recommend using Malwarebytes. You can download, install, and scan your computer for free. Then you can uninstall it if you’d like. Open the app and look in the Help menu for the Uninstall command.
Final thoughts
If you get an “out of application memory” message, don’t panic. It just means your workbench has gotten too crowded. A quick restart is usually all it takes to clean things up. And if the problem keeps coming back, check for updates or find someone who can help you solve the problem. If you’re a client of mine I invite you to book an appointment with me so that we can fix the problem.
