Parallel Programming Guide for HP-UX Systems

Introduction to parallel environments
Parallel programming model
Chapter 1 7
Parallel programming model
Parallel programming models provide perspectives from which you can write—or adapt—code
to run on a high-end HP system. You can perform both shared-memory programming and
message-passing programming on an SMP.
The shared-memory paradigm
In the shared-memory paradigm, compilers handle optimizations, and, if requested,
parallelization. Numerous compiler directives and pragmas are available to further increase
optimization opportunities. Parallelization can also be specified using POSIX threads
(Pthreads). Figure 1-1 shows the SMP model for the shared-memory paradigm.
Figure 1-1 Symmetric multiprocessor system
The message-passing paradigm
HP has implemented a version of the message-passing interface (MPI) standard known as
HP MPI. This implementation is finely tuned for HP technical servers.
CPU CPU CPU CPU
Memory
I/O
Symmetric multiprocessor system