Java and Parallelism II?
Thus “Java plus message passing” form of parallel computing is actually somewhat easier than in Fortran or C.
- Java has been integrated with PVM and MPI using either pure Java or with Java wrappers to existing implementations
Coarse grain parallelism very natural in Java and we have discussed how to use this with RMI (see WebFlow example)
“Data Parallel” languages features are NOT in Java and have to be added extending ideas from HPF and HPC++ etc
- e.g. NPAC’s HPJava translates to Java+Messaging just as HPF translates to Fortran plus message passing
Java has built in “threads” and a given Java Program can run multiple threads at a time (see work of Gannon’s group)
- In Web use, allows one to process Image in one thread, HTML page in another etc.
- threads can be used to do more general parallel computing but only on shared memory computers