Setting Number of Threads

By default, the number of threads for Intel IPP threaded libraries equals the number of processors in the system. If the value of the OMP_NUM_THREADS environment variable is less than the number of processors in the system, then the number of threads for Intel IPP threaded libraries equals the value of the OMP_NUM_THREADS environment variable.

To configure the number of threads used by Intel IPP internally, call the function ippSetNumThreads(n) at the very beginning of an application. n is the desired number of threads (1, ...). To disable internal parallelization, call ippSetNumThreads(1).

Getting Information on Number of Threads

To find the number of threads created by the Intel IPP, call function ippGetNumThreads.

Optimization Notice

The Intel® Integrated Performance Primitives (Intel® IPP) library contains functions that are more highly optimized for Intel microprocessors than for other microprocessors. While the functions in the Intel® IPP library offer optimizations for both Intel and Intel-compatible microprocessors, depending on your code and other factors, you will likely get extra performance on Intel microprocessors.

While the paragraph above describes the basic optimization approach for the Intel® IPP library as a whole, the library may or may not be optimized to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include Intel® Streaming SIMD Extensions 2 (Intel® SSE2), Intel® Streaming SIMD Extensions 3 (Intel® SSE3), and Supplemental Streaming SIMD Extensions 3 (Intel® SSSE3) instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors.

Intel recommends that you evaluate other library products to determine which best meets your requirements.


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