SPEC ACCEL Benchmark Description File

Benchmark Name


Benchmark Author

Serial C version was developed the Center for Manycore Programming at Seoul National University and derived from the serial Fortran versions in "NPB3.3-SER" developed by NAS.

Initial port to OpenMP by Alexander Grund

Benchmark Program General Category

Block Tridiagonal Solver for 3D PDE

Benchmark Description

BT solves a 3D discretization of Naiver-Stokes equation: Ku=r where u and r are 5x1 vectors defined at the points of a 3D rectangular grid and K is a 7 diagonal block matrix of 5x5 blocks. K = BTx * BTy * BTz where BTx, BTy and BTz are block tridiagonal matrices of 5x5 blocks in x, y and z directions, respectively. The main iteration loop of BT starts from the computation of r (compute_rhs) followed by successive inversion of BTx, BTy and BTz (x_solve, y_solve and z_solve) and the result is stored in the main variable u.

Input Description

The input dataset size is comprised of W, A, B classes.

Test: class W reference data for 24X24X24 grids after 200 time steps,

Train: class A reference data for 64X64X64 grids after 200 time steps

Ref: class B reference data for 102X102X102 grids after 200 time steps

Output Description

It prints out the 5x1 vector in u.

Programming Language


Threading Model


Known portability issues



  1. Information on NPB 3.3, including the technical report, the original specifications, source code, results and information on how to submit new results, is available at: http://www.nas.nasa.gov/Software/NPB/
  2. Information about the C version developed by the Center for Manycore Programming can be found at: http://aces.snu.ac.kr/Center_for_Manycore_Programming/Home.html