Adjust swap space size on Ubuntu

Intro

Today, while running a Non-uniform Refinement job in CryoSPARC, the task was terminated unexpectedly. After some research, it appeared the process may have been killed by the system because of insufficient memory.

There are two ways to increase memory: spend money on more of it, or add swap space.

Since most tasks in the workflow don't have high memory requirements, and the task log indicated that only a small amount of additional memory was needed, I decided to try increasing the swap space first.

Detailed procedure

The following instructions are from ChatGPT4 and have been verified to work, with minor edits for readability.

Open a terminal and disable the current swap file:

BASH

sudo swapoff -a

Create or resize the swap file with either dd or fallocate. fallocate is faster, but not all file systems support it.
1. Example using fallocate to resize the swap file to 8GB:
  BASH
  sudo fallocate -l 8G /swapfile
2. If your system doesn't support fallocate, use dd instead:
  BASH
  sudo dd if=/dev/zero of=/swapfile bs=1G count=8 # `bs=1G` indicates that each time a 1GB is written，`count=8` indicates that 8GB total written。
Set the permissions on the swap file so that only root can read and write:

BASH

sudo chmod 600 /swapfile

Set up the file as a swap file:

BASH

sudo mkswap /swapfile

Enable the new swap file:

BASH

sudo swapon /swapfile

Make the swap setting persistent

To retain the swap setting after the system restarts, add it to the /etc/fstab file. Open /etc/fstab and add the following line:

BASH

/swapfile swap swap defaults 0 0

This way, the swap file is enabled automatically each time the system boots.

Note

It seems that the /swapfile entry already exists in /etc/fstab, so you can optionally skip the last step.

Outro

After increasing the swap space from 2G to 8G, the task was completed successfully. 800 CNY saved—a good day.