Developer Guide

  • 2021.1
  • 12/04/2020
  • Public Content

Overview of the Intel Optimized HPCG

The Intel® Optimized High Performance Conjugate Gradient Benchmark (Intel® Optimized HPCG) provides an implementation of the HPCG benchmark ( optimized for Intel® Xeon® processors and Intel® Xeon Phi™ processors with Intel® Advanced Vector Extensions (Intel® AVX), Intel® Advanced Vector Extensions 2 (Intel® AVX2), Intel® Advanced Vector Extensions 512 (Intel® AVX-512) support. The HPCG Benchmark is intended to complement the High Performance LINPACK benchmark used in the TOP500 ( system ranking by providing a metric that better aligns with a broader set of important cluster applications.
The HPCG benchmark implementation is based on a 3-dimensional (3D) regular 27-point discretization of an elliptic partial differential equation. The implementation calls a 3D domain to fill a 3D virtual process grid for all the available MPI ranks. HPCG uses the preconditioned conjugate gradient method (CG) to solve the intermediate systems of equations and incorporates a local and symmetric Gauss-Seidel preconditioning step that requires a triangular forward solve and a backward solve. A synthetic multi-grid V-cycle is used on each preconditioning step to make the benchmark better fit real-world applications. HPCG implements matrix multiplication locally, with an initial halo exchange between neighboring processes. The benchmark exhibits irregular accesses to memory and fine-grain recursive computations that dominate many scientific workloads (for details, see
The Intel® Optimized HPCG contains source code of the HPCG v3.0 reference implementation with necessary modifications to include:
  • Intel® architecture optimizations
  • Prebuilt benchmark executables that link to
    • Inspector-executor Sparse BLAS kernels for sparse matrix-vector multiplication (SpMV)
    • Sparse triangular solve (TRSV)
    • Symmetric Gauss-Seidel smoother (SYMGS)
that are optimized for Intel AVX, Intel AVX2, and Intel AVX-512 instruction sets. For the Intel AVX-512 instruction set, there are separate versions that target Intel® Xeon® Scalable processors and Intel® Xeon® Phi processors. Use this package to evaluate the performance of distributed-memory systems based on any generation of the Intel® Xeon® processor E3, Intel® Xeon® processor E5, Intel® Xeon® processor E7, Intel® Xeon® Scalable processor family, and Intel Xeon Phi
processor families.
Intel® oneAPI
Math Kernel Library
Inspector-executor Sparse BLAS kernels SpMV, TRSV, and SYMGS are implemented using an inspector-executor model. The inspection step chooses the best algorithm for the input matrix and converts the matrix to a special internal representation to achieve high performance at the execution step.
Optimization Notice
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and 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. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.
Notice revision #20110804
This notice covers the following instruction sets: SSE2, SSE4.2, AVX2, AVX-512.

Product and Performance Information


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