Performance evaluation of cache allocation technology for NFV noisy neighbor mitigation

A major challenge with Network Functions Virtualisation (NFV) is ensuring protection of Virtual Network Function (VNF) resources against "Noisy Neighbor" effects. This is essentially the result of shared resources being consumed in extremis within a multi-tenant setup, meaning one VNF's resources are restricted by that of another VNF. One of the major shared resource bottlenecks is the central processor's Last Level Cache (LLC)- this paper details a testbed which enables "Cache Allocation Technology" (CAT), so as to deterministically prioritize LLC resources between competing workloads. A number of CAT "Class of Service" (CoS) paradigms are explained for a range of service chain scenarios, involving virtual Firewall and virtual Router VNFs alongside a Noisy Neighbor VNF. Significant performance benefits are confirmed bringing the performance of target VNFs in the presence of a LLC-hungry Noisy Neighbor, into alignment with the baseline scenario of a "Noise-Free" neighboring VNF.