def _GetEnvironmentVars(benchmark_spec):
  """Return a string containing HPCG-related environment variables.

  Args:
    benchmark_spec: benchmark spec

  Returns:
    string of environment variables
  """
  return ' '.join([
      'NUM_GPUS=%s' % benchmark_spec.total_gpus,
      'OMP_NUM_THREADS=%s' % benchmark_spec.cpus_per_rank
  ])