組件	描述
User state CPU	The actual amount of time the CPU spends running the users program in the user state. It includes time spent executing library calls, but does not include 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 the use of blocking for I/O transfers.
I/O Time and Network Time	These are 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.

性能工具：

UNIX提供了重要的工具來測(cè)量和微調(diào)Unix系統(tǒng)的性能：

命令	描述
nice/renice	Run a program with modified scheduling priority
netstat	Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships
time	Time a simple command or give resource usage
uptime	System Load Average
ps	Report a snapshot of the current processes.
vmstat	Report virtual memory statistics
gprof	Display call graph profile data
prof	Process Profiling
top	Display system tasks

您可以使用聯(lián)機(jī)幫助幫助這里提到的每個(gè)命令的語法檢查完成。