Howto enable and configure ZRAM

This tutorial aims to provide steps to enable and configure ZRAM on Linux Mint.

The tutorial has been tested on Linux Mint 21.3 and 22.1 CE - but should equally work on Ubuntu, Debian, LM Debian Edition and similar.

1. What is ZRAM? Is it any good?
Wikipedia provides a summary description about ZRAM: https://en.wikipedia.org/wiki/Zram
In short: When used for swap, ZRAM allows Linux to make more efficient use of RAM. This is particularly nice on machines that do not have much RAM - or for running applications that require a huge amount of RAM (like certain demanding games).
ZRAM is part of the Linux kernel. It is enabled by default on Android/ Chromebooks/ PopOS / Fedora.

2. Enable ZRAM
a) Install zram-tools:
zram-tools provides tools and scripts to enable and configure zram.

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sudo apt-get install zram-tools

b) Adapt the config file:

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sudo nano /etc/default/zramswap

Uncomment the following lines and save the document:

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ALGO=lz4         #use ALGO=zstd  on systems with less than 4 GB of RAM
PERCENT=50

c) Optimize options for the use of swap on ZRAM:
Since ZRAM behaves differently than ordinary disk swap, we have to configure the system's swap to take full advantage of ZRAM:

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sudo nano /etc/sysctl.conf

At the end of the file, add the following line for better performance and save the file.
Page-cluster = 3 is the default, when using swap on an HDD or SDD drive.
Page-cluster = 0 should be set when ZRAM is enabled - this is also the default on Android/ Chromebooks/ PopOS.

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vm.page-cluster = 0

Save this file.

3. Reboot your system

4. Check if everything works as expected:
The following commands might be helpful:

Check the status of zramswap:

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sudo systemctl status zramswap.service

Provide information on zram:

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zramctl

Show information on swaps (including zram):

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swapon

Check options:

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cat /proc/sys/vm/page-cluster       #should be 0
cat /sys/block/zram0/comp_algorithm     #should be the same as configured by ALGO= in /etc/default/zramswap

5. Have fun!

6. If you want to disable ZRAM:
In order to disable, just
1. Uninstall zram-tools:

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sudo apt remove zram-tools

2. Open the file /etc/systctl.conf:

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sudo nano /etc/sysctl.conf

- In this file, delete (or comment) the line that starts with vm.page-cluster
- Save this file
3. Reboot.

Last edited by goebbe on Mon Jul 14, 2025 10:50 am, edited 1 time in total.


Source: https://forums.linuxmint.com/viewtopic.php?t=427964