Swap space is used to free chunks (pages) of memory from the RAM. This is needed when the physical memory is running out, or when pages initially created by a program are not needed any more. There are two types of swap space: swap partition and swap file.
More flexible than swap partition and well supported today. May not be the best choice on old fragmented hard disk though.
- As root, create the swap file:
fallocate -l 4G /swapfile chmod 600 /swapfile mkswap /swapfile
- Activate the swap file:
- Optionally make it available when system starts, in /etc/fstab, add:
/swapfile none swap defaults 0 0
- If you need to delete it:
swapoff -a rm /swapfile
Server specific things
Scaleway provides a script that does exactly above, with the exception of adding the swap file to the fstab. The script can be used like this:
/usr/local/sbin/scw-swapfile start # create and activate a 4GB swap file in /swapfile /usr/local/sbin/scw-swapfile stop # de=activate and delete /swapfile
If you need an different swap file size, you can edit SWAPFILE_SIZE in the script.