Towards Fine-grained Resource Allocation in NFV Infrastructures

Resource optimization arguably comprises a crucial aspect for Network Function Virtualization (NFV) infrastructures. In this respect, the problem of virtualized network function (VNF) placement commonly entails the selection of the most appropriate server within a single or among multiple Points-of-Presence (PoPs). Nevertheless, CPU cache hierarchy and memory locality in NUMA multi-core servers along with the diversity in NFV resource profiles introduce significant challenges in terms of intra-server resource allocation; a problem that is often overlooked. As such, we stress on the need for fine-grained resource allocation in NFV infrastructures, and, to this end, we study various aspects of CPU allocation for VNF chains. We deem this intra-server resource allocation problem as complementary to the large body of literature that seeks to optimize VNF placement onto virtualized infrastructures. More particularly, we shed light on the intra-server VNF placement problem, treating CPU cores as the main resource allocation unit. To this end, we assess the performance of multiple CPU allocation combinations under varying server utilization levels and processing workloads with diverse requirements in terms of CPU and memory. Our experimentation approach lets us progressively gain useful insights, which ultimately form ground rules that can be leveraged for optimized server resource allocation.