BIL406-Chapter-11-MIMD Programming Languages.ppt
- 2. Chapter 11 MIMD Programming Languages • 11.1 Concurrent Pascal • 11.2 Communicating Sequential Process CSP • 11.3 occam • 11.4 Ada • 11.5 Sequent C • 11.6 Linda, • 11.7 Modular P
- 3. Introduction • Only procedural, parallel programming languages for MIMD systems will be dealt with in this chapter. • • Non-procedural parallel (functional and logic languages) are treated in next chapters. • • The most important concepts are discussed and further explained with programming examples (The individual languages are only briefly introduced).
- 4. 11.1 Concurrent Pascal • The language is a parallel extension of the sequential programming language (Except OCCAM, all others are an extend of an existing sequential language). • The Most important parallel concepts of concurrent Pascal are: • 1. The introduction of the process concept (declaration of process types and corresponding variables, the processes). • 2. The synchronization of parallel processes via monitors with conditions (here called queue). • 3. The introduction of classes (abstract data types).
- 5. 11.2 Communicating sequential process CSP • A system consist of a number of parallel processes. • Each process is executed sequentially, and they communicate via data exchanges as necessary. • Since all synchronization and communication between processes in CSP is handled via messages, there is no need for semaphores or monitors (Guarded command for communication).
- 6. Parallel language constructs • Page 95 • • Program (page 95-96) • • Program for volume control 1(page 96) • • In order to allow a single process to send different messages to VolCon, the example program has to be changed considerably. • • Program for volume control 2 (page 97)
- 11. 11.3 occam • The occam language is a direct commercial successor of CSP, and was developed by Inmos for transputers. • Parallel Language construct. • Page 98 • v := e assign the value of expression e to variable v, • c ! e output the value of expression e to channel c, • c ? v input from channel c to variable v. • Alan figure 7 • SEQ sequential execution: component executed one after the other.
- 18. • PAR parallel execution: components executed concurrently. • ALT alternative execution: first component ready is executed. • Alan page 15. • Example (page 99). • • Page 99-100 • • Program for volume control
- 25. 11.4 Ada • Language Constructs • • Page 101 • • Program for volume control (page 102) • • Example Program(page 103)
- 30. 11.5 Sequent C • Parallel library functions • Page 104, • Sample Program page 104 • • Figure 9.1 shows execution of the sample program. • Example of iteration inside of Child Processes: • • Program page 105. • • Output of the Program page 106.
- 36. 11.6 Linda • Parallel Operations • Page 106 - 107 • Figure 9.2 shows Linda’s tuple space • Example program page 108-109 • When executing a read (RD) or input (IN) operation, three different case can arise • Cases page 109 • Implementation of semaphore by using a Landa primitive • Initialization OUT (“sema”);
- 42. • Pi • …. • IN (“sema”); • <critical section> • OUT (“sema”); • …. • • Program prime number generation page 109-110 • Figure 9.3 shows tuples from the prime number program. • Pros and cons of Linda2s parallel language concepts • Page 110-111
- 46. 11.7 Modula P • In Modula-P there are three types of module : • Processor Modules: The initialization of whole process system is being started in the processor module. • High level modules (regular modules): At this level, individual processes can be declared and started. • Low level modules: This is lower level of a program is only required when real time programming or machine control must be carried out via direct memory addressing. • Page 111-112 (gerekli deği) • Parallel language construct • Page 112-113. • Example of monitor page 113. • Programs page 114-115.