Recommend SWAP size for Linux

SWAP file usage in our Linux distribution is common to most all other Linux versions and so information gained from other systems running Linux should be usable in FreeBSD or Debian.

So to begin, SWAP disk space is used when we begin to run out of main RAM memory, using it just as if it were regular memory.
SWAP space prevents us from running out of memory, which can be a very bad problem should it occur.
SWAP space is also used with the computer function called Hibernate, where all of the computer memory state is saved to your hard disk and can be restored at a later date.

In this article though, we are concerned about its usage as memory.
So, the first thing to decide, is how much should you create, when you install the OS?

If you are like me, you often just go with the default of 2.00 GB or so.
But apparently, there are some basic recommendations for this SWAP file size to be created according to Red Hat recommendations.

Code:
RAM Memory SWAP File Size

Up TO 4GB 2GB
4GB TO 16GB 4GB
16GB TO 64GB 8GB
64GB TO 256GB 16GB

Run command to check space:

free -m
total used free shared buffers cached
Mem: 1877 1690 187 0 8 177
-/+ buffers/cache: 1504 372
Swap: 1999 0 1999