I have Supermicro product; H8DGT-HIBQF, 2 x 6100 and 8x 8GB memories, but I can see IB performance low sometimes.
Please check items below.
4100/6100 CPU Case
: Make PowerNow disabled from BIOS setup
4200/6200 CPU Case
: Make 'HPC mode' enabled from BIOS setup
6100/6200 CPU Case
Please add “numactl --cpunodebind=0,1 --membind=0,1” option into the utilities.