Swap space is a portion of the hard disk that is used as virtual memory by the Linux operating system. It is used when the physical memory (RAM) of the system is full. Swap space can improve the performance of the system by allowing it to store data that is not currently being used in RAM on the hard disk. This frees up RAM for other tasks, which can lead to improved performance.
There are several ways to check the swap space usage on a Linux system. One way is to use the “free” command. The “free” command displays information about the system’s memory usage, including the amount of swap space that is being used.