Does Linux have swap?

You can create a swap partition that is used by Linux to store idle processes when the physical RAM is low. The swap partition is disk space set aside on a hard drive. It is quicker to access RAM than files stored on a hard drive.

How does Linux calculate swap?

If RAM is more than 1 GB, swap size should be at least equal to the square root of the RAM size and at most double the size of RAM. If hibernation is used, swap size should be equal to size of RAM plus the square root of the RAM size.