Operating System Structures

1. Layered Approach

1.1. OS can retain greater control over the computer.

2. Microkernel

2.1. Provide a communication facility

2.2. Benefit of Mikrokernel

2.2.1. Extensibility

2.2.2. Flexibility

2.2.3. Reliability

2.2.4. Portability

3. Communication Models

3.1. Message passing

3.1.1. did not pass directly & use os to pass

3.2. Shared memory

3.2.1. a region memory that is shared by cooperating processes

4. Operating System Services

4.1. User interface

4.2. Program execution

4.3. I/O operations

4.4. File-system manipulation

4.5. Communications

4.6. Error detection

5. System call

5.1. To be used by an application program to invoke a function provided

5.2. Types of system call

5.2.1. Process control

5.2.2. File management

5.2.3. Device management

5.2.4. Information maintenance

5.2.5. Communocations

5.2.6. Protection

6. OS Design Goals

6.1. User goals

6.1.1. convenient,easy to learn,reliable,safe,fast

6.2. System goals

6.2.1. easy to design,implement