OpenMP Programming Model

• Shared Memory, Thread Based Parallelism
• Explicit Parallelism
• Fork Join Model

• Compiler Directive Based
• Nested Parallelism Support
• Dynamic Threads

OpenMP Directives

Fortran Directive Format

• Format Sentinel directive [clause....]
• Sentinel $OMP or C$OMP or $OMP
• Example $OMP PARALLEL DEFAULT(SHARED)
  PRIVATE(BETA,PI)
• General Rules
  • Comments can not appear on the same line as a directive
  • Several Fortran OpenMP directives come in pair and have the
    form shown below
    $OMP directive
    [Structured block of code]
    $OMP end directive

OpenMP Format

C/C++ Directive Format

• Format #pragma omp directive-name [clause....] newline
• Example #pragma omp parallel default(shared) private(beta,pi)
• General Rules
  • Case sensitive
  • Each directive applies to at most one succeeding segment, which must be a structured block