How do I monitor Linux system performance using top?

The top program provides a dynamic, real-time view of the actual process activity on a server. By default, it displays the most CPU-intensive tasks running on the server and updates the list every five seconds.

Commonly Used Hot Keys

The top command provides several useful hot keys:

Hot Key Usage
c Display full command-line arguments for each process. Useful for identifying specific phantoms and java processes.
m Displays memory information off and on.
A Sorts the display by top consumers of various system resources. Useful for quick identification of performance-hungry tasks on a system.
o Enables you to interactively select the ordering within top.
k Issues kill command.

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