A fine-grained network traffic analysis with Millisampler

What this post added

Introduced Millisampler, a new fine-grained network traffic characterization tool. Millisampler uses an eBPF-based tc filter to collect network metrics at configurable high-granularity timescales (100us, 1ms, 10ms), including traffic volumes, active flows, ECN marks, and retransmissions. It employs per-CPU variables to avoid locks and periodic sampling to minimize overhead. The tool has been used to debug network performance issues and characterize traffic patterns, contributing to improved network efficiency and reliability.