173.applu
SPEC CPU2000 Benchmark Description File
Benchmark Name
APPLU
Benchmark Author
Sisira Weeratunga
Benchmark Program General Category
Computational Fluid Dynamics and Computational Physics
Benchmark Description
Solution of five coupled nonlinear PDE's, on a 3-dimensional logically
structured grid, using an implicit psuedo-time marching scheme, based on
two-factor approximate factorization of the sparse Jacobian matrix. This
scheme is functionally equivalent to a nonlinear block SSOR iterative
scheme with lexicographic ordering. Spatial discretization of the
differential operators are based on second-order accurate finite volume
scheme. Insists on the strict lexicographic ordering during the solution of
the regular sparse lower and upper triangular matrices. As a result, the
degree of exploitable parallelism during this phase is limited to O(N**2)
as opposed to O(N**3) in other phases and it's spatial distribution is
non-homogenous. This fact also creates challenges during the loop
re-ordering to enhance the cache locality.
Input Description
There are two approaches to control the memory and run-time requirements of
the benchmark:
-
change in mesh size,
-
change in number of time steps taken.
For a fixed mesh size, run-time varies linearly with the number of time
steps taken. Currently, input decks are available for several different
pairs of mesh cubic sizes and the number of time steps taken. Realistic
workloads would involve meshes that contain in excess of 125,000 mesh
points (i.e., 51X51X51 grid) and at least several hundred time steps.
Output Description
The program is capable of automatically verifying whether a given run
conforms to the specification of the benchmark by using internally stored
reference solutions. However, these reference solutions are available only
for a fixed number of mesh size/time steps pairs. If the input data does
not correspond to any of the internally stored reference solutions, the
verification test is not performed. Otherwise, the output indicates whether
or not the run was successfull in meeting the requirements of the
verifications tests. To conform to the specification of the benchmark, a
run should successfully pass all three verification tests. Failure in any
one or more tests indicates non-conformance with the specifications.
Programming Language
Fortran 77
Known portability issues
None
Reference
E. Barszcz, R. Fatoohi, V. Venkatkrishnan and S. Weeratunga "Solution
of Regular Sparse Triangular Systems on Vector and Distributed-Memory
Multiprocessors", Rept. No: RNR-93-007, NASA Ames Research Center,
1993
http://www.nas.nasa.gov/Pubs/TechReports/ebarszcz/RNR-93-007/RNR-93-007.html
Last Updated: 14 December 1999
