Chapter 1 Operating System
by LIM HONG SHEN
1. Role
1.1. OS is responsible for managing the movement, storage, and processing of data
2. Simple Batch Systems
2.1. I/O devices are slow compared to processor
2.2. Several jobs are kept in main memory at the same time, CPU is multiplexed
3. Time-Sharing Systems
3.1. Handle multiple interactive jobs
3.2. Time is shared among multiple users
4. Parallel Systems
4.1. Sharing same ram & memory
4.2. Advantage
4.2.1. Increased throughput
4.2.2. Econimical
4.2.3. Increased reliability
4.2.3.1. Graceful degradation
4.2.3.2. Fail-soft system
5. Asymmetric Multiprocessing
5.1. Each processor assign a specific task
5.1.1. Master processor schedules and allocates work to slave processors
5.1.2. Slave processor look to master processor for instruction
6. Real-time System
6.1. Hard real-time task
6.1.1. Must meet deadline
6.1.2. or else will cause damage/fatal error
6.1.3. can't accept any delay
6.2. Soft real-time task
6.2.1. Can accept some delay
6.3. Charactetistics
6.3.1. Determinism
6.3.2. Responsiveness
6.3.3. User control
6.3.4. Reliability
6.3.5. Fail-soft Operation
7. A program that controls the execution of applications and hardware.
8. Main Objective:
8.1. Convenience
8.2. Efficiency
8.3. Ability to evolve
9. Symmetric Multiprocessing
9.1. Handle many thing at one times
9.2. No authority level
9.3. Having same rule
10. Distributed Systems
10.1. Each processor has its own local memory
10.2. Advantage
10.2.1. Resources Sharing
10.2.2. Computation speed up - load sharing
10.2.3. Reliability