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core for 22 core). All the snoop modes with the System Profile set to Performance follow similar pattern as DAPC. As
shown in the graph on the right in Figure 1, changing the System Profile from DAPC to Performance can provide up
to 2% performance benefit. The COD.Perf is the best option, about 2-4% better compared to OSB.DAPC across all
processor models. The total 2-4% improvement with COD.Perf is accounted partially due to the change in snoop
mode and partially due to change in the BIOS System Profile to Performance. We ran the car2car benchmark for all
the combinations above with the sse LS-DYNA binary as well and noted similar behavior with the Performance
System Profile and COD snoop mode being 2-6% better than the default OSB.DAPC. The avx2 binaries performed
12-19% better than the sse binaries across all the processor models.
CD-adapco® STAR-CCM+ is another CFD application widely-used by industry for solving problems involving fluid
flows, heat transfer, and other phenomena. The STAR-CCM+ benchmarks results show a pattern similar to LS-DYNA
in terms of snoop mode and System Profile.
Figure 2: Comparing snoop modes for STAR-CCM+
Figure 2 compares the snoop modes for the Civil_20m and Lemans_17m benchmarks. For simplicity, data for these
two benchmarks are shown. The other benchmarks datasets show results similar to the patterns in Figure 2. The
BIOS profile in the graphs is set to DAPC and the snoop modes are compared against the default OSB snoop mode
(which is set at 1, the red line on the graph). The COD is the best option for the Civil_20m benchmark, it is about 2-
3% better for DAPC. For the Performance System Profile COD is 4-6% better for the Civil_20m benchmark (not
shown in the graph). COD is followed by OSB and then ES for smaller core counts. Performance with ES though
starts reducing as the cores increase similar to what was observed with LS-DYNA car2car benchmark case. The
HlMach10 benchmark shows similar pattern to the Civil_20m benchmark. For the HlMach10 benchmark case the
COD.Perf option is 2-7% better than the default OSB.DAPC.
All the other benchmarks (EglinStoreSeparation, Kcs, Lemans_100m, Reactor9m, TurboCharger, Vtm) show similar
pattern to Lemans_17m. The COD and OSB perform similarly, there is only ~1% difference between OSB and COD