Parallel Systems

1. Multiprocessor systems with more than on CPU in close communication.

2. Tightly coupled system – processors share memory and a clock; communication usually takes place through the shared memory.

3. Advantages of parallel system:

a. Increased throughput

b. Economical

c. Increased reliability

* graceful degradation

                        * fail-soft systems

 4. Symmetric multiprocessing (SMP)

a. Each processor runs and identical copy of the operating system.

b. Many processes can run at once without performance deterioration.

c. Most modern operating systems support SMP

5. Asymmetric multiprocessing

a. Each processor is assigned a specific task; master processor schedules and allocated work to slave processors.

b. More common in extremely large systems