Introduction to operating systems

1.1 Objectives and functions of the operating system

1.1.1 The target of the operating system

1. Ease of Access

2. Validity

3. Extensibility

4. Openness

The role of the 1.1.2 operating system

1.OS as the interface between the user and the computer hardware system

2.OS as a manager of computer system resources

3.OS provides an abstraction of computer resources

1.1.3 driving the development of operating system

1. Continuously improve the utilization of computer resources

2. User-Friendly

3. Continuous replacement of devices

4. The continuous development of computer architecture

5. Constantly proposing new application requirements

1.2 Development process of the operating system

1.2.1 Computer systems with no operating system configured

1. Manual operation mode

Cons: User exclusive full machine/cpu waiting for manual operation

2. Offline input/output (off-line I/O) mode

Cons: Reduced CPU idle time/increased I/O speed

1.2.2 Single-channel batch processing system

1. Processing of single-channel batch systems (simple batch precessing system)

2. Characteristics of single-channel batch processing system (1. Automatic 2. Sequential 3. Single-channel)

1.2.3 multi-channel batch systems (multiprogrammed batch processing system)

1. The basic concept of multi-channel program design

It also has several programs in memory and makes them run alternately

2. Advantages and disadvantages of multi-channel batch processing system

(1) High resource utilization

(2) Large system throughput

(3) long average cycle time

(4) No interaction capability

Operating system: A set of programs that effectively organizes and manages computer hardware and software resources, schedules all types of jobs, and facilitates user-friendly use.

1.2.4 Timeshare System (Time sharing systems)

1. Introduction of time-sharing system

(1) Man-Machine interaction (2) shared host

2. Key issues

(1) Timely acceptance (2) Timely processing

3. Characteristics of time-sharing system

(1) Multiplexing (2) Independence (3) timeliness (4) Interoperability

1.2.5 Real Time System

1. Types of real-time systems

(1) Industrial (weapon) control system (2) Information Query System (3) multimedia System (4) Embedded system

2. Comparison of real-time system and CTSS features

(1) Multiplexing (2) Independence (3) timeliness (4) interactivity (5) Reliability

Introduction to operating systems