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Logical Processor - Disabled

Power Supply Redundant Policy - Not Redundant

Power Supply Hot Spare Policy - Disabled

I/O Non-Posted Prefetch - Disabled

Snoop Mode - Opportunistic Snoop Broadcast (OSB), Early Snoop (ES),

Home Snoop (HS), Cluster on Die (COD)

Node interleavin

- Disable

BIOS 2.0.0

iDRAC

Firmware

2.30.30.02

LS-DYNA is a general-purpose finite element program from LSTC capable of simulating complex real-world structural

mechanics problems. We ran the car2car benchmark with end time set to 0.02 with both the single precision avx2

and the single precision sse LS-DYNA binaries.

Figure 1: Comparing snoop modes and BIOS Profiles for LS-DYNA

The left graph in Figure 1 shows how better or worse the different snoop modes perform compared to the default

setting of snoop mode = OSB and BIOS profile=DAPC (which is set at 1, the red line on the graph). Just changing the

snoop mode to COD increases performance by 1-3% with either BIOS profiles across all the processor models. The

performance with COD is closely followed by OSB followed by ES for lower core counts and HS for 16, 20 and 22

core processors. With ES mode, the system starts paying the penalty of having lower request tokens per core for

higher core counts compared to the other snoop modes (for e.g. for 14 cores 128/14 = 9 per core Vs. 128/22 = 5 per