Abstract View of System Components

Operating System Functions

• What is virtual memory (VM) management?
• Operating system allocates portion of hard disk to function like RAM
• Paging

• RAM

• Page
• File

• Virtual Disk

Operating System Functions

• How does an operating system schedule jobs?

• Job
• an operation the
• processor manager

• Receiving data
• from
• input devices

• Sending
• information to
• an output devices

• Processing
• Instructions

• Transferring items
• from storage to
• memory

Operating System Functions

• What is spooling?
• Print jobs sent to buffer instead of directly to printer, where print jobs wait their turn

• 

• Print Queue

• Print Job list

• Jobs to
• be
• printed

• Disk

• Jobs being printed

Operating System Functions

• How does an operating system monitor performance?
• Provides a program
• called performance monitor,
• that assesses and reports
• information about various
• system resources and
• devices.

Operating System Functions

• How does an operating system manage files?
• Includes a program
• called file manager,
• such as Windows
• Explorer.
• Commands
• Copy, Rename,
• Delete, move ...

Operating System Functions

• What is a file allocation table (FAT)?
• a table of information
• that operating system
• uses to locate file on
• a disk.

Operating System Functions

• What are functions of operating system on network?
• Establish network
• connection
• Controlling network
• traffic
• Closing network
• connection

Type of Operating System

• Desktop Operating System
• a program control activities in standalone computer.
• Such as MS-Windows 9X, MS-Windows NT workstation
• MS-Windows 2000 Professional, MS-Windows XP Professional
• Network Operating System
• a program control activities both on local computer and other computer on network.
• Such as MS-Windows NT Server, Windows 2000 Server, MS-Windows 2000 Advance Server, MS-Windows 2003 Server

Operating System Goals

• Users expect certain properties of operating systems
• Efficiency
• Robustness
• Scalability
• Extensibility
• Portability
• Security
• Protection
• Interactivity
• Usability

Operating System Architectures

• Today’s operating systems tend to be complex
• Provide many services
• Support variety of hardware and software
• Operating system architectures help manage this complexity

Review Questions

• What are the main roles of operating system?
• How many type of operating system?
• Explain some of operating system goal.
• Homework
• Brief evolution of operating system