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Academic Days 2005

Windows OS Course Supplement Kit: What should be there?

Arkady RetikMicrosoft

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Presentation Plan

1. Core OS education: is there a problem?

2. What should our goals be?

3. Is our current thinking correct?

4. What’s next?

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What is the problem?

Windows specific:• Use of Windows OS in Core OS courses is low

• Is this a Microsoft only problem?• Why isn’t Linux a solution?

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Operating System courses in general:• CS intake overall is shrinking (USA, UK, ...)• In particular, OS courses are ‘not attractive’

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Why is Windows underutilized?

• No Windows source code (Almost: Windows Source Code is available for ~ 150 Universities WW under Shared Source )

• Current license ‘discourages’ teaching and publication

• Insufficient environment to run software out of the box

• No Windows based instructional system (such as Nachos, MINIX)

• Few Windows OS oriented labs & exercise materials

• Inadequate and outdated textbook coverage of Windows

• No academic oriented reference books of Windows

• Limited academic research publications using Windows

• Windows source footprint is large (~ 50% large than Linux)

• ABM

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Are students interested in OS classes?

• Most of the CS programs offer a core OS class during 2nd or 3rd year of study

• About 90% will not take further OS classes

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Program Goal, Objectives and ScopeOur goal is to develop and deliver a program for computer science and engineering undergraduate and graduate courses that provides modern and up to date OS knowledge by leveraging Microsoft software and products

The program’s top level objectives are:• Offer Windows based teaching and learning, tools and materials• Promote presence of Windows in OS courses world-wide• Increase knowledge of Windows Internals among students and faculty• Demonstrate the innovations underlying the Windows solutions• Provide infrastructure for the future academic research • Support reproducibility requirements for OS research publications e.g.

OSDI, SOSP • Complement other MS Academic initiatives (Shared Premium Source,

Rotor, WinCE)

Scope: CS OS courses a. Undergrad coursesb. Graduate coursesc. Research and Publications

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Our current thinking

Program components:

1. Limited Source – Alternative to existing Shared Source Premium

a. Simplify current license b. Add tools out of DDK that academics can use to rebuild the kernelc. Textbook: Internals book acceptable to CS faculty

2. OS Project Course (Project OZ) – New offering

a. Undergrad projects based on NT Kernel APIs b. Uses NT subsystem model, with licensed wrapper for NTAPIs (no

Windows sources)c. C/C++, C#, and maybe Java supportd. Companion lab project book will supplement OS textbook

3. Curriculum Development Kit (CDK) – New offering

a. Aimed at teaching OS coursesb. Provides ACM/IEEE Core OS curriculum content

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Background

Connecting NT and Shared Source:

Brief History and Architecture overview

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OS Evolution

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History of NT

Team forms November 1988

Developers from DEC and Microsoft

Build from the ground up

• Advanced PC Operating System

• Designed for for desktops and servers

• Secure, scalable SMP design

• All new code

Initial effort targeted at Intel i860 code-named N10, hence the name NT which doubled as N-Ten and New Technology

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NT Timeline first 15 years

2/1989 Coding Begins

7/1993 NT 3.1

9/1994 NT 3.5

5/1995 NT 3.51

7/1996 NT 4.0

12/1999 NT 5.0 Windows 2000

8/2001 NT 5.1 Windows XP

3/2003 NT 5.2 Server 2003

4/2004 NT 5.2 Windows XP 64 Bit Edition

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Goal Setting

High level goals:

• Portability – Ability to target more than one processor, avoid

assembler, abstract away machine dependencies.

• Reliability – Nothing should be able to crash the OS. Anything that

crashes the OS is a bug.

• Extensibility – Ability to extend the OS over time

• Compatibility – With DOS, OS/2, POSIX, or other popular runtimes.

• Performance – All of the above are more important than raw speed!

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NT Architecture

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Overview of Windows Architecture

NT is not a microkernel, but does support user-mode OS personalities (i.e. for posix, OS/2, Win32)

Primary supported programming interface: Win32

Win32 and other subsystems built on native NT APIs

NT APIs generally not documented (not intended as the supported programming model) – but specific APIs are documented in the DDK

Kernel implementation organized around the object manager

NT APIs are rich (many parameters) and need re-factoring and simplification for student use

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Windows Architecture

User-mode

Kernel-mode Trap interface / LPC

ntdll / run-time library

Win32 GUIProcs & threads

Kernel run-time / Hardware Adaptation Layer

Virtual memoryIO ManagerSecurity refmon

Cache mgr

File filters

File systems

Volume mgrs

Device stacks

Scheduler

Kernel32 User32 / GDI

DLLs

Applications

System Services

Object Manager / Configuration Management

FS run-time

exec synchr

Subsystemservers

Login/GINA

Critical services

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Windows Kernel Organization

Kernel-mode organized into

NTOS (kernel-mode services)

– Run-time Library, Scheduling, Executive services, object manager, services for I/O, memory, processes, …

HAL (hardware-adaptation layer)

– Insulates NTOS & drivers from hardware dependencies

– Providers facilities, such as device access, timers, interrupt servicing, clocks, spinlocks

Drivers

– kernel extensions (primarily for device access)

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Major Kernel Services

Process managementProcess/thread creation

Security reference monitorAccess checks, token management

Memory managerPagefaults, virtual address, physical frame, and pagefile

managementServices for sharing, copy-on-write, mapped files, GC support,

large appsLightweight Procedure Call (LPC)

Native transport for RPC and user-mode system services. I/O manager (& plug-and-play & power)

Maps user requests into IRP requests, configures/manages I/O devices, implements services for drivers

Cache managerProvides file-based caching for buffer file system I/OBuilt over the memory manager

Scheduler (aka ‘kernel’)Schedules thread execution on each processor

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OS Project Course(code name Project OZ)

(see examples of the projects in the Appendix)

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The Project OZ Course

Objectives

• Provide an environment to build a rich set of projects that explore OS principles by leveraging the NT subsystem model for implementing OS personalities

• Use real OS features rather than a ‘toy’ simulation• Reduce the complexity required to learn / build

experiments

• A simple development environment, using standard

tools for building, debugging, and instrumentation• Encourage ‘out-of-the-box’ thinking by students

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The Project OZ Course

OZ Overview

Library of functions that wrap the native NT APIs to provide access to low-level primitives to provide address spaces, threads, exceptions, and IPC

Languages: C/C++, C#, Java

A runtime of support functions that simplify student projects

Documentation for the OZ functions/runtime

A rich set of projects, with many variations, that allow students to explore qualitatively (& quantitatively) a large assortment of OS principles

Tools for instrumentation and measurement

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CDK

22What will CDK cover?CDK modules

1. cover all OS topics (based on Windows XP/Server 2003) 2. scaleable to multiple levels3. modular (can be used in whole / in part). Basic Module will provide materials to incorporate into a complete basic level

OS course of one semester in length. The module will cover the Windows OS specific topics in the core and elective units of the OS BOK of Computing Curricula 2001.

Advanced Module will provide materials to incorporate into an advanced level OS course of one semester in length. The module will cover the Windows OS specific topics in the core and elective units of the “CC2001” OS BOK as well as relevant Networking and other units.

All curriculum materials (syllabi, course outlines, lecture notes, labs, exercises, etc.) will be available in the MSR Curriculum Repository.

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What OS Body of Knowledge topics will CDK cover?

a. Core topics OS1. Overview of operating systems OS2. Operating system principles OS3. Concurrency OS4. Scheduling and dispatch OS5. Memory management

b. Elective topicsOS6. Device managementOS7. Security and protectionOS8. File systemsOS9. Real-time and embedded systemsOS10. Fault toleranceOS11. System performance evaluationOS12. Scripting

c. Advanced topics A13. Windows networking A14. Comparing the Linux and Windows Kernels A15. Windows – Unix Interoperabilityd. Labs and Exercises to reinforce the topics

Anything

else?

24What will CDK consist of?

• Instructor’s material:1. An exemplar course syllabus and outline.2. Classroom materials (i.e. lecture slides, notes and other

supporting materials). 3. Lab exercises, assignments and testing materials with notes,

manuals and instructions. 4. Software tools referenced in lecture materials or used in labs or

exercises. 5. Copy of Windows Internals 4th edition MS Press book.

• Student material:Any material that should be delivered to student by professor (i.e. lab assignments, lab set up and descriptions, tools use instructions) will be part of Instructor’s material as stand alone ‘redist’ packages. Windows Internals 4th edition will be a recommended textbook for the course.

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How do we achieve best content and top quality?

Engage the best available experts

Tailor to the academic style and requirements

Conform to the latest ACM/IEEE Computing Curricula – de facto educational standard 

Capitalize  on 4th Edition Windows Internals book - best Windows reference material

Build on rich experience of Microsoft OS training and experienced OS faculty

Validate by independent and randomly selected academic reviewers: WW pilot.   

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What’s next Our current plans to provide initial input for next

academic year (see Appendix for specific topics):

Core topics will be available early July 2005

Elective topics will be available in Fall 2005

Will be looking for participants in pilots and trials

If you are interested - let your academic contact and me know:

arkadyr@microsoft.com

Leave your business card /contact details

More information – watch this space in June: Shared Source

http://www.microsoft.com/resources/sharedsource

Curriculum Repository on MSDN AA

http://www.msdnaa.net/curriculum

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Appendix: Support Information

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Teaching Core OS Classes

Theoretical

Courses

MixedCourses

Practical

Courses

few labs labs many labs

Sysadmin/programming System programKernel modify System programOS design lab

reso

urc

es

teach

ing

reso

urc

es

pro

duct

sA

cadem

ic

papers

CDK ProjectOZ

Windows

CE/XPe

Shared

Source

Advanced Courses Research

Textb

ooks

/Pro

ject

Books

~50% ~15-20%~30-35%

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Virtual PC

http://www.microsoft.com/windowsxp/virtualpc/

• Virtual PC 2004 as a tool for running several

versions of Windows simultaneously on one machine. • It could also be used to run one or more independent Unix (or Linux, Natchos, etc)

sessions as hosted operating systems under Windows. You don’t have to reboot, an OS can crash without taking Windows down, and each session runs real Unix (or Windows, if you choose).

• The virtualized file system allows you to wipe out changes made during a session, so you can experiment without rendering the OS unbootable. And every Virtual PC-hosted OS automatically inherits (through virtualization) all of the devices and networking you’ve set up for Windows.

• It gives us exactly what we need – and also allow students and teachers utilize their Windows machines.

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What is our approach?

Faculty requirements:

Comprehensive, modular and up-to-date curricula & content:

• Continuation of subjects / Spiral learning / Non-prescriptive

• Flexible in levels (institutions; courses) and delivery (web-based teaching)

• Cool topics and technology to attract and retain students (e.g. Gaming Technology, Mobility, Embedded, Web development, Robotics, etc. )

• Multidisciplinary topics (engineering; business)

• Reference material and textbooks

to provide content in three areas:

1. undergraduate, 2. graduate, 3. research and publications

University Requirements

Meet existing curriculum accreditation & industry recognition guide lines:

• USA: ACM/IEEE ‘Body of Knowledge’

• WW: varies by country (incl. government/industry requirements)

Motivators:

• Incentive to Faculty 1. Modern, best teaching OS, easy to introduce; modular offerings; saves work (No special lab equipment - use Virtual PC)

2. Software Engineering tools (Dev. Analysis and Test Tools)

3. Research/publication potential“Why should I change my material?”

• Incentive to Students 1. Employability 2. Engaging3. Up to date knowledge

“Will this class help me to get a job or a place in Graduate School?”

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CDK Core Topics – available in early July 2005

Overview of Operating Systems – (Core) OS1• Windows Operating System Internals Course Overview (Core)• The Evolution of Operating Systems (Core)• Windows Operating System Family – Concepts & Tools (Core)

Operating System Principles – (Core) OS2• Structuring of the Windows Operating System (Core)• The Windows API – Naming Conventions, Types (Core)• History of the Windows NT/2000/XP/2003 operating system (Core)• OS Principles labs, quizzes, and assignments

Concurrency – (Core) OS3• Critical Sections, Semaphores and Monitors (Core) • Windows Object Manager, Trap Dispatching, Synchronization (Core)• Windows Inter-process Communication (Core/Advanced)• Concurrency labs, quizzes, and assignments

Scheduling and Dispatch – (Core) OS4• The Concept of Processes and Threads (Core)• Windows Processes and Threads (Core)• Windows Process and Thread Internals (Core/Advanced)• Windows Thread Scheduling (Core) • Advanced Windows Thread Scheduling (Core/Advanced)• Scheduling and Dispatch labs, quizzes, and assignments

Memory Management – (Core) OS5• Memory Management for Multiprogramming (Core)• Windows Memory Management Internals (Core)• Windows Memory Structures (Core)• Advanced Windows Memory Management (Core/Advanced)• Memory Management labs, quizzes, and assignments

Protection and Security – (Elective) OS7• The Security Problem (Elective) • Windows Security Components and Concepts (Elective)• Windows Security Descriptors (Elective/Advanced)• Security labs, quizzes, and assignments

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CDK elective & supplementary topics – available in Fall 2005

Device Management - The Input/Output System – (Elective) OS6• Principles of I/O Systems (Elective)• The Windows I/O System Components (Elective)• Windows I/O Processing (Elective/Advanced)• Device Management labs, quizzes, and assignments

File System – (Elective) OS8• Background: Unix File Systems (Elective)• The Windows File System (NTFS) (Elective)• Encrypting File System Security in Windows OS (Elective/Advanced)• NTFS – Recovery Support (Elective/Advanced)• Windows File and Directory Management (Elective)• File System labs, quizzes, and assignments

Real-time and Embedded Systems – (Elective) OS9• Introduction and Vocabulary (Elective) • Real-Time Systems with Windows (Elective)• Embedded Systems with Windows XP Embedded (Elective)

Fault-tolerance (Elective) OS10 System Performance Evaluation and Troubleshooting (Elective) OS11Scripting (Elective) OS12

SUPPLEMENTARY UNITSWindows Networking – (Supplementary/Advanced)

• Networking Components in Windows OS (Supplementary/Advanced)• Windows Socket Programming (Supplementary/Advanced)• Microsoft-specific extensions to Sockets and other Networking APIs (Supplementary/Advanced) • Networking labs, quizzes, and assignments

Comparing the Linux and Windows Kernels (Supplementary/Advanced)Windows – Unix Interoperability (Supplementary/Advanced)

• File and Command Interoperability (Supplementary/Advanced)• Programming (Supplementary/Advanced)

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Project OZ examples by Dr. Dave Probert

(in no particular order)

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Loading Program Images

Take the sections in a file and load into an address space• dynamic relocation• shared libraries• creating stacks and initial thread contexts• create environment and other parental state• Initialize IO descriptors from parent

Using• NtCreateProcess to create an NT process container• NT VM to manage/modify process contents• NT library functions to take apart images and set environment• NT thread APIs to execute thread in new process• NT handle duplication to set IO descriptors

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System Calls

Communicate requests for system services• implement basic system calls• access data cross domains• parameter validation and penetration testing• asynchronous operations• servicing models

Using• NT LPC to perform RPC• NT VM to access/modify child process state• NT threads to support flow-of-control

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Manage address spaces, physical memory & ptes

Build data structures for managing VM-related resources• basic data structures and algorithms• support various page-table models

Using• NT VM to implement actual mappings (and shared memory) for

address spaces• NT VM to implement dirty bits• NT VM shared memory provides page sharing and simulates

physical pages with virtual pages• NT threads provide DMA (for IO)

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Implementing Virtual Memory

Build various kinds of virtual memory systems• use previous resource management for addresses, mem, page

tables • page file organization• replacement algorithms• shared memory, object/file-backed memory regions• IO/DMA simulation• performance measurement of algorithms

Using• NT LPC/exceptions to handle page faults• NT VM to control actual mappings• NT IO for access to page file

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Create Processes

Implement processes• create/delete processes in the Oz world • use loader project for loading programs• experiment with different models for process creation and program

execution• implement handle tables for referencing objects• manage run-down and synchronization issues

Using• NT processes to create real VM state (but for little else)

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Create Threads / Scheduling

Implement threads• create/delete threads in an Oz process • build appropriate data structures to represent thread• tie into Oz process data structures• create stacks and manage thread execution context (PCB)• experiment with ideas like scheduler activations• implement a scheduler, using different policies, priorities, etc• add multi-processor support

Using• NT threads to represent processors and execute Oz threads on NT

threads (Oz threads are essentially user-mode threads)• NT APCs (Asynchronous Procedure Calls) to deliver timer

interrupts to running Oz threads

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Synchronization

Implement various synchronization primitives• build user-mode, kernel-mode, and hybrid synchronization

primitives of various kinds (events, rw locks)• extend Oz scheduler to support blocking of threads• experiment with deadlock issues, priority inversion

Using• NT compare&swap primitives

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Other project areas

IO Architecture

File Systems

Networking

System bootstrap

Performance measurement & instrumentation (e.g. tracing)

Error handling

Exceptions and traps, stack unwinding

Management of physical resources

Management of resource sharing policies

NUMA multiprocessors

Security, authentication, ACLs

Object support

Namespaces

Virtual machines