Swap space may be a swap partition, a swap file or a combination of the two. One should size swap space to be at least twice the size of the computer's RAM. (but less than 2GB)
dd if=/dev/zero of=/swapfile bs=1024 count=265032 - Create file filled with zeros of size 256Mb
mkswap /swapfile - Create swap file
swapon /swapfile - Begin use of given swap file. Assign a priority with the "-p" flag.
swapon -s - List swap files
cat /proc/swaps - Same as above
This example refers to a swap file. One may also use a swap partition. Make entry to /etc/fstab to permanently use swap file or partition.
/swapfile swap swap defaults 0 0
Note: To remove the use of swap space, use the command swapoff. If using a swap partition, the partition must be unmounted.