bottom (btm) vs Monit

bottom is a free graphical system and process monitor that runs in a terminal on Linux, macOS and Windows. It charts CPU use for each core and as an average, along with RAM and swap over time. Network and disk I/O are graphed too, with a control for zooming the displayed time interval. Its process widget lets users display, sort and search process information, use tree mode and send kill signals. Other widgets show disk capacity and use, temperature sensors and battery use. Appearance and behavior can be changed through command-line options or a configuration file, including themes, layout, widget behavior and filtering. An htop-inspired basic mode offers a simpler view, and a selected widget can be expanded to fill the terminal. A read-only option blocks actions that affect the system, such as stopping processes. Installation is documented through package managers, Cargo and pre-built release binaries. Official platform support covers macOS, Linux and Windows; architecture support varies by system. Android and some other systems may work unofficially with limited testing and support.

Monit is a free, open-source utility for managing and monitoring Unix systems, available for Linux, macOS, and self-hosted deployment. It watches local daemon processes and can restart a stopped process or stop one using too many resources. It checks files, directories, and filesystems for timestamp, checksum, or size changes, and tests TCP, UDP, and Unix domain sockets using protocols such as HTTP and SMTP. Scheduled program or script checks can trigger actions or alerts based on exit values. Monit tracks CPU, memory, system load, and network interfaces, and sends customizable error alerts to syslog or its own log. Its HTTP(S) interface displays service status and allows process control and monitoring changes. It works with init, upstart, and systemd, can use existing run-level scripts, and can run as PID 1 in containers. The maker says it uses statically linked OpenSSL 3.5.7 and dynamically linked PAM support.