Load Balanced Source Teaming Policy Mode Aware of NUMA

The NSX Load Balanced (LB) Source Teaming Policy mode defined for N-VDS (E) becomes aware of NUMA when the following conditions for VNF-C are met:

• The Latency Sensitivity configuration for the VNF-C is set to High.

• The network adapter type used by the VNF-C is VMXNET3.

If you deploy and power on a VNF-C that has the above conditions met, the Load Balanced Source Teaming policy triggers NSX to check the VNF-C NUMA placement and aligns its logical cores with the VNF-C NUMA placement.

For deterministic performance of data plane workloads, uniform NUMA node design and NUMA-aware Load Balanced Source Teaming is crucial. This ensures that the same number of logical cores and NICs can be made available to VNF-C, irrespective of the NUMA node to which VNF-C is pinned by the ESXi scheduler.

The Load Balanced Source teaming policy does not consider NUMA awareness to align VNF-Cs and NICs in the following conditions:

• The LAG uplink is configured with NICs from multiple NUMA nodes.

• The VNF-C has affinity to or spans over multiple NUMA nodes.

• The ESXi host failed to determine NUMA information for either VNF-C or NICs.

Under the above conditions or if the Load Balanced Source Teaming policy is not used, NUMA vertical alignment could be enforced manually for the data plane VNF-Cs. This is done by setting the parameter numa.nodeAffinity for the VNF-C to the correct NUMA node.

Summary of Recommendations:

• For automatic NUMA vertical alignment, replicate the NUMA node configuration in terms of NIC placement and logical core assignment to N-VDS (E) across all NUMA nodes, and use Load Balanced Source teaming policy.

• If needed, set numa.nodeAffinity for VNF-C to the same NUMA node as that of logical cores and NIC.