System Monitoring

top

• Provides a dynamic view of system processes and resource usage.

top

htop

• It is an Interactive Process Viewer.
• Enhanced version of top.

htop

vmstat

• It displays information about processes, memory, paging, block IO, traps, and CPU activity.

vmstat

iostat

• It displays information about CPU and I/O statistics.

iostat

free

• It displays free and used memory in the system.

free

df

• It shows disk space usage in a human-readable format.

df

du

• It summarizes disk usage of a directory and its contents.

du -sh /path/to/directory