This is the reference version of CloverLeaf version 1.3.
CloverLeaf 1.3 contains a number of optimisations over previous releases. These include a number of loop fusion optimisations and the use of scalar variables over work arrays. Overall this improves cache efficiency.
This version also contains some support for explicit tiling. This is activated through the two input deck parameters:
tiles_per_chunkTo specify how many tiles per MPI ranks there are.tiles_per_problemTo specify how many global tiles there are, this is rounded down to be an even number per MPI rank.
Expected performance is give below.
If you do not see this performance, or you see variability, then is it recommended that you check MPI task placement and OpenMP thread affinities, because it is essential these are pinned and placed optimally to obtain best performance.
Note that performance can depend on compiler (brand and release), memory speed, system settings (e.g. turbo, huge pages), system load etc.
| Test Problem | Time | Time | Time |
|---|---|---|---|
| Hardware | E5-2670 0 @ 2.60GHz Core | E5-2670 0 @ 2.60GHz Node | E5-2698 v3 @ 2.30GHz Node |
| Options | make COMPILER=INTEL | make COMPILER=INTEL | make COMPILER=CRAY |
| Options | mpirun -np 1 | mpirun -np 16 | aprun -n4 -N4 -d8 |
| 2 | 20.0 | 2.5 | 0.9 |
| 3 | 960.0 | 100.0 | |
| 4 | 460.0 | 40.0 | 23.44 |
| 5 | 13000.0 | 1700.0 |
| Node Count | Time |
|---|---|
| 1 | 40.0 |
| 2 | |
| 4 | |
| 8 | |
| 16 |
| Node Count | Time | Speed Up |
|---|---|---|
| 1 | 1700 | 1.0 |
| 2 | ||
| 4 | ||
| 8 | ||
| 16 |