That'll be useful for a swap partition, but if you're using a swap file instead of a partition it won't work.

To clarify, a swap file is just a file on your hard drive the size you'd like your swap to be. Filled, at the start, with zeros. You still put it in your fstab to mount it but instead of a full partition, it's just a file.

This makes it more flexible, and easy to change the size of or turn it off or on during operation, safer to change the size (less steps, less ramifications, lower chance of data loss), or have it expand as needed, but is more restrictive in other features while being a bit slower and less secure.

Windows has a similar system for swap called a pagefile.

On linux, while there is a gui to change a swap partitions size, changing the swap files size has no gui. Even though it is, theoretically, a simpler operation. Simply run swapoff, delete the old file, create the new file, run swapon. No partition managment needed, essentially no chance of data loss