Datasheet
SYSTEM OVERVIEW
3
◆
Press Windows+R to open the Run dialog box, then enter
TASKMGR
and press Enter.
◆
Press Ctrl+Alt+Del and select Start Task Manager from the menu on the Login/Logoff
screen.
Figure 1.1
The Task Manager
has been upgraded
to give more detailed
information.
Windows gives you so many different ways to get to the Task Manager because the Task
Manager allows you to kill errant processes and bring a server back to life. The information that the
Task Manager presents to you is one of the best tools you have in improving the performance of
Windows Server.
The Windows operating system examines processes, and decomposes them into the fundamen-
tal units of execution, which are called threads. Threads are assigned priorities and then added to
the scheduling of the execution queue. Through context switching, all processes get access to the
processor according to their priority, something that is often referred to as time slicing. When a pro-
cess allows it, Windows can decompose the process into multiple threads, optimizing the process-
ing and improving the process’s performance (known as multithreading). Windows is capable of
managing the event queue for a single process or to multiple processors through a Symmetric
Multi-Processor (SMP) scheme. With time slicing, it appears that the system is doing multiple tasks
at the same time, or multitasking, but that is only the net result of individual steps that are execut-
ing too quickly to be differentiated. The effect a user sees is akin to viewing a movie.
Windows 2000/NT Architecture
In its original conception, Windows NT was built as a modular system with two distinct layers.
What the user sees and works with was called the user mode, and all hardware I/O was contained
in modules that are part of the kernel mode. The kernel mode isolates programmatic control of
hardware from the user mode, thus making the system both more stable and more secure. These
two different layers were designed to execute in separate memory addresses, further isolating
the User mode from direct hardware control. Figure 1.2 shows a schematic of the Windows 2000
operating system.
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