Swap Manager

The Swap Manager in Modularitea allows you to enable or disable swap memory on your TeaLinuxOS system with a single toggle. This guide explains what swap is, when you need it, and how to manage it.

What Is Swap?

Swap is a form of virtual memory that extends your physical RAM by using a portion of your storage (disk or RAM-backed block device) as overflow space. When your RAM is full, the operating system moves less-used data from RAM to swap, freeing RAM for active processes.

TeaLinuxOS uses ZRAM for swap, which is different from traditional disk-based swap:

FeatureTraditional SwapZRAM Swap (TeaLinuxOS)
LocationDisk partition or swap fileCompressed block device in RAM
SpeedLimited by disk I/O speedNear-RAM speed (much faster)
CompressionNoneZSTD compression (typically 2–3x ratio)
Disk usageConsumes disk spaceZero disk space used
ConfigurationPartition or file + fstab entryzram-generator.conf + systemd

ZRAM swap works by creating a compressed region in RAM. For example, with a 2:1 compression ratio, 4 GB of data can fit in 2 GB of physical RAM — effectively expanding your usable memory without touching the disk.

When Is Swap Needed?

You Should Enable Swap If:

  • Your system has 4 GB or less of RAM — Swap provides critical overflow space to prevent out-of-memory crashes.
  • You run memory-intensive applications — IDEs, browsers with many tabs, virtual machines, and compilation jobs can easily exceed physical RAM.
  • You want system stability — Without swap, the Linux OOM (Out of Memory) killer may terminate applications abruptly when RAM is exhausted.
  • You use hibernation — Some hibernation mechanisms require swap space.

You Might Disable Swap If:

  • Your system has 16 GB or more of RAM — With ample RAM, you may never need swap under normal workloads.
  • You are benchmarking — Disabling swap ensures all operations run in physical RAM for consistent performance measurements.
  • You understand the risks — Running without swap means the OOM killer will activate immediately when RAM is exhausted.

Advantages and Disadvantages

Advantages of Swap

AdvantageDescription
Prevents crashesApplications are less likely to be killed by the OOM killer
Extends usable memoryZRAM compression effectively increases available memory
Zero disk impactZRAM swap does not use disk space or cause disk wear
FastCompressed RAM is much faster than disk-based swap
AutomaticOnce enabled, swap works transparently in the background

Disadvantages of Swap

DisadvantageDescription
CPU overheadCompression and decompression use CPU cycles
Reduced available RAMThe ZRAM device itself uses some RAM for the compressed store
Not infiniteZRAM cannot compress all data equally; incompressible data fills swap quickly

How to Use the Swap Manager

Checking Swap Status

  1. Open Modularitea.
  2. Click the Settings button (⚙️) at the bottom of the sidebar.
  3. Locate the Swap Memory card.
  4. The card displays the current swap status: Enabled or Disabled.

Enabling Swap

  1. If swap is currently disabled, toggle the switch to On.
  2. A PolicyKit authentication dialog will appear — enter your administrator password.
  3. Wait for the confirmation notification.
  4. Swap is now active.

Disabling Swap

  1. If swap is currently enabled, toggle the switch to Off.
  2. Authenticate with your administrator password.
  3. Wait for the confirmation notification.
  4. Swap is now disabled.

Verifying Swap Status

You can verify swap status from the terminal:

swapon --show

If swap is enabled, you will see output similar to:

NAME       TYPE      SIZE USED PRIO
/dev/zram0 partition   4G   0B  100

If swap is disabled, this command produces no output.

You can also check the ZRAM configuration file:

ls -la /etc/systemd/zram-generator.conf

If the file exists, swap is configured. If the file does not exist, swap is disabled.

Technical Details

How It Works

When you toggle swap in Modularitea:

  1. The GUI calls the Tauri backend’s set_swap_mode command with "enable" or "disable".
  2. The backend invokes pkexec modularitea-swap <on|off>.
  3. The modularitea-swap binary (from tealinux-modularitea-libs) runs with root privileges.
  4. Enable: Creates /etc/systemd/zram-generator.conf and starts the ZRAM device via systemd.
  5. Disable: Removes /etc/systemd/zram-generator.conf and deactivates the ZRAM device.
  6. The binary outputs a JSON result indicating success or failure.
  7. The GUI displays the appropriate notification.

Configuration File

When swap is enabled, the configuration file at /etc/systemd/zram-generator.conf defines the ZRAM parameters, including:

  • The compression algorithm (ZSTD)
  • The size of the ZRAM device

Why Administrator Password Is Required

Creating and removing files in /etc/systemd/ and manipulating block devices requires root access. Modularitea uses pkexec to safely escalate privileges only for this specific operation.

Warnings

⚠️ Risk of system instability. Disabling swap on a system with limited RAM (4 GB or less) may cause the Linux OOM (Out of Memory) killer to terminate running applications without warning. This can result in data loss. Only disable swap if you have sufficient RAM for your workload.

⚠️ ZRAM uses RAM. While ZRAM is faster than disk swap, it still uses a portion of your physical RAM for the compressed block device. On very low-RAM systems (2 GB), enabling ZRAM swap may slightly reduce the RAM available for applications, though the net effect of compression is usually positive.

⚠️ Changes are persistent. Enabling or disabling swap through Modularitea is a persistent change that survives reboots. You do not need to toggle swap again after restarting your system.