Table of contents

What is a swap space

I ran into an issue where building a NextJS app on Docker would take forever. Then, I found out I could solve this by adding a swap space to my Ubuntu VPS.

So what is a swap space?

Swap space is a designated area on a hard drive (HDD or SSD) that acts as an extension of a computer’s physical RAM. When the RAM is full, the operating system moves inactive or less frequently used data from RAM to this swap space to free up memory for active tasks. This process is known as “swapping.”

How to create a swap space

To create a swap file on an Ubuntu Linux VPS for building a Docker and NextJS application, follow these steps:

Check existing swap space:
```
sudo swapon --show
```
If this command returns no output, you don’t have any swap space configured.
Create swap file
```
sudo fallocate -l 2G /swapfile
```
This creates a 2GB swap file (it worked in my case). Adjust the size as needed.
Set permissions
```
sudo chmod 600 /swapfile
```
This restricts access to root only, enhancing security.
Set up swap area
```
sudo mkswap /swapfile
```
This formats the file as swap space.
Activate swap
```
sudo swapon /swapfile
```
This enables the swap file.
Make swap permanent Edit /etc/fstab:
```
sudo nano /etc/fstab
```
Add this line:
```
/swapfile none swap sw 0 0
```
This ensures the swap file is mounted on reboot.
Verify swap:
```
sudo swapon --show
```
This should now display information about your new swap space.

After that, running my docker build script worked just fine!