nmon vs PM2

nmon is a free Linux tool for systems administration, tuning, and performance benchmarking. It collects system information and presents live readings in a terminal through a curses interface. Keyboard controls let operators turn individual data categories on or off. The display can include CPU, memory, network, disks, filesystems, NFS, top processes, and, in the Linux version, resources and processors. Captured readings can be written to a comma-separated file for later analysis or longer-term recording. nmonchart converts output into webpage graphs, while nmon Analyser loads files into Excel and creates graphs. njmon injectors can add JSON data to InfluxDB and Splunk, with real-time graphing through InfluxDB and Grafana. Binaries are listed for POWER, x86, x86_64, mainframe, and ARM Linux. Unsupported distributions require compiling with GCC and the ncurses development library. The Linux project is GPLv3; AIX nmon is integrated into topas and is not open source.

PM2 is a daemon process manager for managing applications and keeping them online. PM2 Runtime is an open-source process manager; PM2 Plus adds monitoring for Node.js production applications. Runtime supports cluster mode, zero-downtime reloads, watch and restart, startup scripts, log management and memory-based reloads. For containers, pm2-runtime can run Node.js applications with process fallback, flow control, monitoring and source-map support. PM2 Plus lists a web monitoring interface, application overview, issue tracking, custom metrics, server health checks and Node.js V8 monitoring. Its alerts include email and Slack notifications, while Enterprise adds rule-based alerting. The AI Assistant connects Claude, Cursor and other MCP-compatible assistants to monitoring data through OAuth with a PM2.io account. Documentation covers Docker, cloud providers, Heroku, AWS Elastic Beanstalk, Nginx and deployment workflows. Runtime costs nothing, and Plus costs $79 a month.