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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.

Swap Partition


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:
swapon /swapfile
  • 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.