chapter 2: computer system structures

1. Storage structure

1.1. main memory

1.2. secondary storage

2. Dual-mode operation

2.1. all resources are shareable

2.2. modes of operation

2.2.1. user mode

2.2.2. kernel mode

3. I/O protection

3.1. all I/O instructions are privileged instructions

3.2. only OS can issue the instructions

4. Interrupt handling

4.1. OS is responsible to carry address to interrupt vector table

4.2. OS temporarily store the data

5. Storage Hierarchy

5.1. speed

5.2. cost

5.3. volatility

5.4. caching

5.4.1. magnetic disk

5.4.2. main memory

5.4.3. cache

5.4.4. hardware register

6. synchronous I/O structure

6.1. only one I/O run at a time

6.2. can't support multiple processes

7. Asynchronous I/O structure

7.1. can support multiple I/O processing

7.2. CPU more efficient

8. Memory Protection

8.1. base register

8.2. limit register

9. hardware address protection

9.1. OS allowed to load user's programs in user's memory

10. CPU Protection

10.1. load timer only can be issue by OS

11. Computer-system operation

11.1. Each device controlleris in charge of a specific type of device .

11.2. Each device controller has a local buffer