Developer Guide

Developer Guide for Intel® oneAPI Math Kernel Library Linux*

ID 766690
Date 7/13/2023
Public

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Document Table of Contents

Configuring Parameters

The most significant parameters in HPL.dat are P, Q, NB, and N. Specify them as follows:

  • P and Q - the number of rows and columns in the process grid, respectively.

    P*Q must be the number of MPI processes that HPL is using.

    Choose PQ.

  • N – the problem size:

    NOTE:

    Increasing N usually increases performance, but the size of N is bounded by memory. In general, you can compute the memory required to store the matrix (which does not count internal buffers) as 8*N*N/(P*Q) bytes, where N is the problem size and P and Q are the process grids in HPL.dat. A general rule is to choose a problem size that fills 80% of memory.

  • NB – the block size of the data distribution.

    The table below shows the recommended values of NB and element sizes for the CPU version:

    Processors

    Intel® Distribution for LINPACK* Benchmark

    Intel® Optimized HPL-AI* Benchmark

    Intel® Xeon Processor supporting Intel® Advanced Vector Extensions (Intel® AVX) instructions or older architecture 256 256
    Intel® Xeon Processor supporting Intel® Advanced Vector Extensions 2 (Intel® AVX2) instructions 192 192
    Intel® Xeon Processor supporting Intel® Advanced Vector Extensions 512 (Intel® AVX-512) instructions 384 384
    Intel® Xeon Processor supporting Intel® Advanced Vector Extensions 512 (Intel® AVX-512) instructions with Intel® Deep Learning Boost and bfloat16 384 768
    Intel® Xeon Processor supporting Intel® Advanced Vector Extensions 512 (Intel® AVX-512) instructions with Intel® AMX bfloat16 384 1536
    Element size 8 bytes 4 bytes

    The table below shows the recommended values of NB and element sizes for the GPU version:

    Processors

    Intel® Distribution for LINPACK* Benchmark

    Intel® Optimized HPL-AI* Benchmark

    Intel® Data Center GPU Series 384 1152 or 1536
    Element size 8 bytes 2 bytes