A Timestamp-Based Pacing Method for Virtual Network Functions

Traffic bursts, particularly at microsecond scale, have emerged as a significant challenge in modern networks utilizing Virtual Network Functions (VNFs). While VNFs employ various acceleration techniques to achieve hardware-comparable performance, including poll-mode APIs, batch processing, and hardware offload features, these optimizations inherently introduce microbursts into network traffic. Traditional solutions like packet pacing at host endpoints or Time-Sensitive Networking (TSN) techniques prove inadequate for VNF environments, as they either focus solely on host-side bursts or require high-precision timestamps that negate the performance benefits of packet acceleration. This paper presents an improved pacing method that maintains effectiveness while significantly reducing overhead. Our main contributions include: (1) an adaptive packet arrival time series acquisition method that adjusts sampling precision based on queue length dynamics, (2) a novel delay estimation method that minimizes forwarding latency while maintaining effective pacing, and (3) mathematical proof of our method's effectiveness. Our simulation demonstrates that the proposed solution can effectively reduce traffic bursts while introducing minimal additional latency across various deployment scenarios.