Tang: tracing found 12s latency

- Engineer Tang flagged a production debugging case where tracing exposed a multi-service latency hotspot that pure logs missed because of abstraction layers. - The concrete example cited was roughly 12 seconds of added latency distributed across eight services, which tracing spans revealed as a chained bottleneck. - That 12s multi-service path shows why span-level tracing is essential to find cross-service race conditions and to map out where agents stall in workflows. (x.com)