How is memory usage displayed?

Memory usage is displayed in the output of the top command in a Linux system. The relevant section shows the total memory, used memory, free memory, and memory used for buffers/cache. Here's a breakdown of the memory usage display:

• MiB Mem: This line shows the total memory available, how much is free, how much is used, and how much is used for buffers/cache.
  • total: Total amount of physical memory.
  • free: Amount of memory that is not being used at all.
  • used: Amount of memory that is currently being used.
  • buff/cache: Memory used by the kernel for buffers and cache.

For example, you might see something like this in the top output:

MiB Mem : 1975.1 total, 1558.7 free, 180.4 used, 236.1 buff/cache

This indicates that out of 1975.1 MiB of total memory, 1558.7 MiB is free, 180.4 MiB is used, and 236.1 MiB is being used for buffers/cache.