Zero-Code Instrumentation of an Envoy TCP Proxy using eBPF I recently had to debug an Envoy Network Load Balancer , and the options Envoy provides just weren't enough. We were seeing a small number of HTTP 499 errors caused by latency somewhere in our cloud , but it wasn't clear what the bottleneck was. As a result, each team had to set up additional instrumentation to catch latency spikes and…