Field notes
Field notes
These notes come from sittings, not from a catalogue of general advice. They concern the boring materials of the work: clocks, status codes, sampled lines, and the difference between a timeout and an application error. If you are sending a log window, start with the piece on what to bring.
Timeouts that look like errors, errors that look like timeouts
Gateway status codes flatten different failures. A briefing that uses one ink for 502, 504, and a hung stream will send the next change window to the wrong file.
What to send before a traffic review
A usable sample is not a screenshot. Clocks, route names, duration fields, and a stripped payload matter more than the reddest hour.
How to read a nine-minute error burst
A burst is a weather event with a start minute and an end minute. Treating it as a daily error rate hides the only hours that mattered.
The gateway’s p95 is not the upstream’s p95
Why a latency percentile taken at the gateway and the same percentile taken on the application are different numbers, and how we draw both when the export allows it.