Mounted oncolumn is our disk in this case. We have plenty of space available in this example (only 1.4G used). Your usage will probably be different.
swapfilein our root (/) directory.
fallocateprogram. This command instantly creates a file of the specified size.
freeutility again to corroborate our findings:
/etc/fstabfile in case anything goes wrong:
/etc/fstabfile by typing: