Processes refer to the running applications that are consuming system resources Resources such as CPU and memory There are parent processes and child processes An application can start another application, this is called parent process All the resources are identified with a unique ID (PID) This PID is assigned on creation and remains the same throughout its life ps, top, htop commands are commands to view the running processes kill and pkill commands are commands to terminate a running process
ps is used to display information about the running processes. It includes information like, PID, command name, memory and CPU usage... the user started the process, start date, time running etc ps aux → displays processes with detailed information ps -u kronos → displays processes owned by kronos user ps --pid=31009 → displays information about specific process STAT column → the current status of the process R → running, S → sleeping, D → Disk sleep Z → Zombie, T → Stopped , I → idle, → High priority
top command is a very good tool to see the running processes It automatically updates the information z → shows colors 1 → toggles between single and combined CPU view f → select which fields to show s → sets the update interval h → shows help q → quits top