OMPNUMTHREADS
OMPNUMTHREADS is commonly encountered as a shorthand reference to the OpenMP environment variable that controls the default number of threads used in parallel regions. The standard and portable name is OMP_NUM_THREADS; OMPNUMTHREADS is not part of the OpenMP specification and is typically not recognized by conforming implementations. Users should rely on OMP_NUM_THREADS for predictable behavior.
What it does: OMP_NUM_THREADS sets the default thread count for parallel regions that do not specify a
How to set: The variable can be defined before launching a program, for example by exporting OMP_NUM_THREADS=4
Scope and interactions: OMP_NUM_THREADS applies to the current process and its children unless overridden. It interacts
Compatibility: Supported by major OpenMP implementations (GCC/LLVM, Intel, IBM, MSVC, and others). Users should ensure the
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