本教學的目的是引進性能分析師提供的免費工具，來監視和管理UNIX係統的性能，以及如何診斷和修複性能問題在Unix環境提供指引。

UNIX具有以下主要資源類型，需要進行監測和調整：

• CPU

• 內存

• 磁盤空間

• 通信線路

• I/O 時間

• 網絡時間

• 應用程序

性能組件：

有以下主要的五個組成部分的係統總時間的推移：

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量和微調Unix係統的性能：

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

您可以使用聯機幫助幫助這裡提到的每個命令的語法檢查完成。