How to Fix High Memory Usage on Linux

What Causes This?

High memory usage on Linux usually happens when too many apps, services, or browser tabs are running at the same time, or when one process has a memory leak and keeps consuming RAM. It can also be caused by startup apps, background sync tools, virtual machines, or outdated software that does not release memory properly. On systems with limited RAM, even normal multitasking can quickly push usage too high and force the system to use swap, which slows everything down.

Common Symptoms

• The system feels slow even when only a few apps are open
• Apps take a long time to open or switch between
• The hard drive or SSD stays busy because Linux is using swap
• The desktop freezes briefly or becomes unresponsive
• Browser tabs or larger apps crash unexpectedly

How to Fix It Manually

1. Check which apps are using the most memory.

   1. Open a terminal.
   2. Run:

      top

      or:

      htop

   3. Look for processes with high %MEM usage.
   4. If htop is not installed, you can usually install it with:

      sudo apt install htop

      on Debian or Ubuntu-based systems.

2. Close or restart memory-heavy apps.

   1. If you find a browser, IDE, VM, or other app using too much RAM, save your work first.
   2. Close the app normally.
   3. If it does not close, end it from the terminal with:

      kill PID

      Replace PID with the process ID from top or htop.
   4. If needed, force it:

      kill -9 PID

3. Disable unnecessary startup and background apps.

   1. Open your desktop environment’s startup applications tool.
   2. On Ubuntu, search for Startup Applications from the app menu.
   3. Disable apps you do not need launching automatically, such as chat tools, cloud sync clients, or update helpers.
   4. Reboot and check whether memory usage improves.

4. Check memory and swap usage directly.

   1. In Terminal, run:

      free -h

   2. Review the used, available, and swap values.
   3. If swap usage is high even with few apps open, a background process may be consuming memory over time.

5. Find and stop unneeded services.

   1. List running services with:

      systemctl --type=service --state=running

   2. Look for services you recognize but do not need.
   3. Stop one with:

      sudo systemctl stop service-name

   4. Disable it from starting automatically if appropriate:

      sudo systemctl disable service-name

   5. Be careful not to disable critical system services unless you know what they do.

6. Update your system and restart.

   1. Install pending updates:

      sudo apt update && sudo apt upgrade

   2. If you use Fedora:

      sudo dnf upgrade

   3. Restart the computer after updates.
   4. If high memory usage started recently, this can fix buggy packages or drivers causing leaks.

Fix It Automatically with Kudu

If you do not want to track down memory-heavy apps and services manually, Kudu can scan for unnecessary background load, clutter, and common performance issues automatically. It gives you a faster way to reduce system strain and improve responsiveness without digging through processes one by one.

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