The Windows NT 2000 XP Kernel Part I.ppt

Windows NT Kernel - An Overview The Windows NT/2000/XP KernelPart I Mostly taken from: Silberschatz – Chapter 21 Nutt – Chapter 21 Windows NT/2000/XP 32-bit preemptive multitasking operating system for Intel microprocessors Key goals for the system: portability security POSIX compliance multiprocessor support extensibility international support compatibility with MS-DOS and MS-Windows applications Uses a micro-kernel architecture NT Kernel History In 1988, Microsoft decided to develop a “new technology” (NT) portable operating system that supported both the OS/2 and POSIX APIs Originally, NT was supposed to use the OS/2 API as its native environment but during development NT was changed to use the Win32 API, reflecting the popularity of Windows 3.0 NT Kernels Windows NT version 4 – 1997 Windows 2000 – 2000 Windows XP – 2001 Windows 2003 - 2003 Design Principles Extensibility — layered architecture Executive, which runs in protected mode, provides the basic system services On top of the executive, several server subsystems operate in user mode Modular structure allows additional environmental subsystems to be added without affecting the executive Portability —can be moved from on hardware architecture to another with relatively few changes Written in C and C++ Processor-dependent code is isolated in a dynamic link library (DLL) called the “hardware abstraction layer” (HAL) Design Principles (Cont.) Reliability —uses hardware protection for virtual memory, and software protection mechanisms for operating system resources Compatibility — applications that follow the IEEE 1003.1 (POSIX) standard can be complied to run on NT without changing the source code Performance —subsystems can communicate with one another via high-performance message passing Preemption of low priority threads enables the system to respond quickly to external events Designed for symmetrical multiprocessing International support — supports different locales via the national language suppor