Parallel Computing
- Computers rely on interconnected CPUs and/or memory units
- Increase processing speed
- Four general forms
- Bit level
- Based on increasing word size of computer
- 8-bit processor --> 16-bit processor, etc.
- Increasing the word size reduces the number of operations on data values larger than the word size
- Current trend is to use 64-bit processors
- Instruction level
- Data level
- Single-instruction, multiple-data-stream (SIMD)
- Single set of instructions can be run on different data sets at the same time
- Relies on control unit directing multiple arithmetic logic units to carry out same operation
- Effective when same process needs to be applied to many data sets
- E.g. increasing the brightness of an image involves adding a value to every pixel
- Task level
- Multiple-instruction, multiple-data-stream (MIMD)
- Different processors can execute different tasks on the same or different data set
- Analogous to pipelining in a von Neumann architecture
Computer Science