Consuming JSON means the familiar iperf3 text layout has to be rebuilt, so a
pure formatter turns each event back into a line — binary units for transfer
totals, decimal units for bitrates, matching how iperf3 quotes each. The view
model keeps the interval series and the end summary as data alongside the
transcript, and a stat row shows current/total, mean, peak and sample count
off that series. A chart can be driven from the same list without re-parsing
text.
Repaints are coalesced on a 250ms timer rather than one per event. Reports can
now arrive several times a second across many streams, and each rebuild
re-renders the whole transcript, so notifying per event made the cost of
drawing scale with the report rate — which competes with the test itself for
CPU and skews the measurement.
Warm-up intervals (-O) are marked omitted by iperf3 and are kept out of the
series so they cannot drag the mean down.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>