Trace replay and calibration

Trace replay has two separate axes:

• Workload replay: recorded arrivals, sessions, prompt prefix structure, and optionally output token ids.
• Timing replay: either sampled from a fitted latency model, replayed verbatim from recorded step gaps, or replaced with explicit timing knobs.

Keeping those axes separate is important. You can replay a captured workload while testing a latency model fit from a different capture, or you can serve the same recorded token stream with synthetic timing for fast client tests.

The trace files used to build the committed figures live under traces/, which is gitignored. See traces/README.md for the local inventory and which captures are fitting inputs versus gate seeds.

Start with Concepts for terminology, then use the scenario pages for arrival replay, prefix-cache workloads, content-identical replay, and multi-token step replay.