How to change the Swappiness of your Linux system

Introduction

Swappiness is a Linux kernel parameter that determines how often the system swaps data from RAM to the swap space on the hard disk. By default, Linux systems have a swappiness value of 60, which means that the system will start swapping data when RAM usage exceeds 40%. In this guide, we’ll walk you through the step-by-step process of changing the swappiness of your Linux system to optimize performance.

Prerequisites

Before you begin, make sure you have the following:

• A Linux system (e.g., Ubuntu, CentOS, Debian)
• Root or sudo access to the system

Step 1: Check Current Swappiness

Open a terminal on your Linux system and run the following command to check the current swappiness value:

cat /proc/sys/vm/swappiness

Step 2: Temporary Swappiness Change

To temporarily change the swappiness value, you can use the sysctl command. For example, to set the swappiness value to 10, run:

sudo sysctl vm.swappiness=10

This change will take effect immediately, but it’s only temporary and will be reset when you reboot your system.

Step 3: Permanent Swappiness Change

To make the swappiness change permanent, you need to modify the /etc/sysctl.conf configuration file. Open the file in a text editor:

sudo nano /etc/sysctl.conf

Add the following line at the end of the file to set the swappiness value:

vm.swappiness=10

Save and close the file. Then, apply the changes by running:

sudo sysctl -p

Step 4: Verify Swappiness Change

Run the following command to verify that the swappiness value has been changed:

cat /proc/sys/vm/swappiness

Conclusion

Congratulations! You’ve successfully changed the swappiness of your Linux system to optimize performance. Adjusting the swappiness value can help improve responsiveness and reduce disk I/O, especially on systems with limited RAM.