Performance Enhancements

The Intel® oneAPI Math Kernel Library has been optimized by exploiting both processor and system features and capabilities. Special care has been given to those routines that most profit from cache-management techniques. These especially include matrix-matrix operation routines such asdgemm().

In addition, code optimization techniques have been applied to minimize dependencies of scheduling integer and floating-point units on the results within the processor.

The major optimization techniques used throughout the library include:

• Loop unrolling to minimize loop management costs

• Blocking of data to improve data reuse opportunities

• Copying to reduce chances of data eviction from cache

• Data prefetching to help hide memory latency

• Multiple simultaneous operations (for example, dot products in dgemm) to eliminate stalls due to arithmetic unit pipelines

• Use of hardware features such as the SIMD arithmetic units, where appropriate

These are techniques from which the arithmetic code benefits the most.