User State CPU

The actual amount of time the CPU spends running the users’ program in the user state. It includes the time spent executing library calls, but does not include the time spent in the kernel on its behalf

System State CPU

This is the amount of time the CPU spends in the system state on behalf of this program. All I/O routines require kernel services. The programmer can affect this value by blocking I/O transfers

I/O Time and Network Time

This is the amount of time spent moving data and servicing I/O requests

Virtual Memory Performance

This includes context switching and swapping

Application Program

Time spent running other programs – when the system is not servicing this application because another application currently has the CPU

nice/renice

Runs a program with modified scheduling priority

netstat

Prints network connections, routing tables, interface statistics, masquerade connections, and multicast memberships

time

Helps time a simple command or give resource usage

uptime

This is System Load Average

ps

Reports a snapshot of the current processes

vmstat

Reports virtual memory statistics

gprof

Displays call graph profile data

prof

Facilitates Process Profiling

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Displays system tasks