Advanced Computer Engineering

							Advanced Computer Architectures                                    Tutorial work/Revision checklist 2.

Parallel Computing

1.    Difference between true and pseudo parallelism (i.e. multitasking or timesharing).

2.    Flynn's classification of parallel architectures on the basis of instruction streams and data
      streams. Associated diagrams. Guideline only! SISD is not a parallel architecture! SIMD is
      vector processing and hence specialised (but powerful and used). MISD is very special (systolic
      arrays), but also used. MIMD is the general case and so needs further classifying to make sense.

3.    MIMD, again as a guide only, differentiated into close coupled (with access to common
      memory) and loose coupled (with own memory) systems. Relevant applications.

4.    Each of the above is further decomposed into bus based or switch based systems. Lots of detail
      about how the resulting 4 broad kinds of general purpose parallel system can be implemented.
      This division is only a guide and there is quite a bit of overlap between these categories and also
      many examples of 'one off' designs which don't really fit into the scheme above. Examples are
      in the textbooks but not covered in the unit.

5.    Need to understand basic principles of switches, mappings (including permutation mappings
      and special permutations such as shuffle/exchange) network topology (diameter concepts etc),
      scaling, all as a basis to understand and evaluate the different bus based and switch based
      configurations.

6.    Difference between single stage and multiple stage switched systems.

7.    Loosely coupled systems using different topologies - especially mesh and hypercube
      arrangements, which are most interesting. Scaling properties of these kinds of system.