Low-Overhead Packet Loss Diagnosis for Virtual Private Clouds using P4-Programmable NICs.

Virtual private clouds have become a huge trend because of their cost-efficiency. However, the complex and virtualized nature of clouds limits the ability of cloud tenants to pinpoint and amend performance degradation problems, such as packet drops. Existing monitoring systems are either designed for the physical network or insufficient to present the concrete reason for packet loss with low overhead. In this paper, we present a Packet Loss Diagnosis (PLD) system, a specific monitoring service designed to detect packet drops on cloud networks and report diagnosis information to tenants. PLD is based on the modern capabilities of P4 data plane programmable NICs and has a limited footprint in the network. It provides detailed information that enables tenants to locate and resolve their issues with respect to the abstraction of the services. It also meets the requirements of a monitoring system designed for large-scale multi-tenant clouds. We implemented the proposed scheme in P4 to demonstrate its viability and investigate its performance and overhead through extensive experiments and Mininet simulation. Our results show that PLD ensures full packet drop detection coverage and can notify tenants in real-time while imposing low overhead.