Chapter 12. Performance

Red Hat OpenStack Platform director configures the Compute nodes to enforce resource partitioning and fine tuning to achieve line rate performance for the guest virtual network functions (VNFs). The key performance factors in the network functions virtualization (NFV) use case are throughput, latency and jitter.

Data plane development kit (DPDK) accelerated Open vSwitch (OVS) enables high performance packet switching between physical NICs and virtual machines. OVS 2.7 embeds support for DPDK 16.11 and includes support for vhost-user multiqueue, allowing scalable performance. OVS-DPDK provides line rate performance for guest VNFs.

Single root I/O virtualization (SR-IOV) networking provides enhanced performance characteristics, including improved throughput for specific networks and virtual machines.

Other important features for performance tuning include huge pages, NUMA alignment, host isolation and CPU pinning. VNF flavors require huge pages and emulator thread isolation for better performance. Host isolation and CPU pinning improve NFV performance and prevent spurious packet loss.

See NFV Performance Considerations and Configure Emulator Threads to run on a Dedicated Physical CPU for a high-level introduction to CPUs and NUMA topology.