SysTutorials

Creating a Swap Partition on Linux

· Q A · updated April 12, 2026

Swap space is essential for system stability, allowing the kernel to move less-frequently-used memory pages to disk when physical RAM is exhausted. Here’s how to set up a dedicated swap partition.

Step 1: Create the Partition

Use fdisk, gdisk (for GPT disks), or parted to create a new partition. For modern systems with GPT partition tables:

sudo gdisk /dev/sdc

At the prompt:

For MBR/DOS partition tables, use fdisk and set the type to 82 (Linux swap).

After creating the partition, verify it exists:

lsblk /dev/sdc

Step 2: Format as Swap

Initialize the partition with the swap filesystem:

sudo mkswap /dev/sdc1

The output will show the swap UUID and size. Keep note of this for later reference.

Step 3: Enable Swap

Activate the swap partition immediately:

sudo swapon /dev/sdc1

Verify it’s active:

swapon -s

Or use the more modern approach with free:

free -h

This shows all swap space currently in use.

Step 4: Persist Across Reboots

Add the swap partition to /etc/fstab so it activates automatically on boot. Edit the file:

sudo nano /etc/fstab

Add this line (using the UUID is more reliable than device names):

UUID=your-swap-uuid    none    swap    sw    0 0

Find your swap UUID with:

lsblk -o NAME,UUID /dev/sdc1

Or check the output from your earlier mkswap command.

Disabling Swap

If you need to remove a swap partition:

sudo swapoff /dev/sdc1

Remove the line from /etc/fstab to prevent it from reactivating on reboot.

Important Considerations

Swap size: A common guideline is 1-2x your RAM on systems with 8GB or less, and 0.5x RAM on larger systems. On modern systems with sufficient RAM, minimal swap (1-2GB) is acceptable.

Swap priority: If you have multiple swap devices, assign priorities in /etc/fstab to control which is used first:

UUID=swap-device-1    none    swap    sw,pri=10    0 0
UUID=swap-device-2    none    swap    sw,pri=5     0 0

Higher priority numbers are used first.

Swappiness: Control how aggressively the kernel uses swap by adjusting the swappiness value (0-100, default 60):

sudo sysctl vm.swappiness=10

Lower values preserve swap for emergencies; higher values use it more readily. Make permanent changes in /etc/sysctl.conf:

vm.swappiness=10

Zram alternative: On systems with limited storage, consider zram instead—compressed in-memory swap that’s faster than disk-based swap. This is configured differently and doesn’t use a partition.

2026 Best Practices and Advanced Techniques

For Creating a Swap Partition on Linux, understanding both the fundamentals and modern practices ensures you can work efficiently and avoid common pitfalls. This guide extends the core article with practical advice for 2026 workflows.

Troubleshooting and Debugging

When issues arise, a systematic approach saves time. Start by checking logs for error messages or warnings. Test individual components in isolation before integrating them. Use verbose modes and debug flags to gather more information when standard output is not enough to diagnose the problem.

Performance Optimization

Security Considerations

Security should be built into workflows from the start. Use strong authentication methods, encrypt sensitive data in transit, and follow the principle of least privilege for access controls. Regular security audits and penetration testing help maintain system integrity.

These complementary tools expand your capabilities:

Integration with Modern Workflows

Consider automation and containerization for consistency across environments. Infrastructure as code tools enable reproducible deployments. CI/CD pipelines automate testing and deployment, reducing human error and speeding up delivery cycles.

Quick Reference

This extended guide covers the topic beyond the original article scope. For specialized needs, refer to official documentation or community resources. Practice in test environments before production deployment.

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