Monitoring memory and swap

Memory is another important component of system performance. All files and data that are currently being used are kept in the system main memory for faster access. The CPU performance also depends on the availability of enough memory. Swap, on the other hand, is an extension to main memory. Swap is part of persistent storage, such as hard drives or solid state drives. It is utilized only when the system is low on main memory.

In this chapter, we will learn how to monitor system memory and swap utilization.

Getting ready

You may need sudo privileges for some commands.

How to do it…

In the last recipe, we used commands top and vmstat to monitor CPU utilization. These commands also provided details of memory usage. Let's start with the top command again:

1. Run the top command and check for the Mem and Swap rows:
   
2. The memory line displays the size of total available memory, size of used memory, free memory, and the memory used for buffers and the file system cache...