The Dell EMC Ready Architecture for Red Hat OpenStack Platform version 16.1 provides the ability to enable NUMA optimization and CPU pinning support on all compute nodes at the core or the edge site(s) in the solution.
Non-Uniform Memory Access or NUMA allows multiple CPUs to share L1, L2, L3 caches, and main memory. When running workloads on NUMA hosts, it is important that the vCPUs executing processes are on the same NUMA node as the memory used by these processes. This ensures all memory accesses are local to the node and thus do not consume the limited cross-node memory bandwidth, adding latency to memory accesses. Similarly, large pages are assigned from memory and benefit from the same performance improvements as memory allocated using standard pages.
For real-time workloads, it is beneficial to control which host CPUs are bound to an instance's vCPUs. This process is known as CPU pinning. No instance with pinned CPUs can use the CPUs of another pinned instance, thus preventing resource contention between instances.