nmon

nmon is a command line tool used to monitor system performance on Unix-like operating systems, such as Linux and AIX. It stands for "Nigel's Monitor" and was developed by Nigel Griffiths, an IBM expert.

nmon provides a comprehensive view of various system resources and performance metrics, including CPU utilization, memory usage, disk I/O, network activity, and process statistics. It can offer real-time monitoring as well as the ability to record data for later analysis.

The tool organizes the collected data into interactive and easy-to-read reports, which can be viewed both in real-time or offline. These reports present detailed information on system performance, displaying graphs, tables, and charts.

nmon offers various customization options to focus on specific areas of interest, filter data, or adjust the reporting interval. It also supports exporting data to external tools or formats, such as CSV or spreadsheet applications.

It is widely used by system administrators, performance analysts, and developers to troubleshoot issues, identify bottlenecks, and optimize system performance. Its command line nature makes it lightweight and convenient to use, especially for remote machines without a graphical user interface.

nmon has gained popularity due to its simplicity, efficiency, and the valuable insights it provides into system performance. It continues to be actively maintained and enhanced by the open-source community, making it a reliable tool for monitoring and understanding system behavior.