Middle truncation: long-name workloadLayout time per round trip (ms)Base45.5Head21.2Sampled fitting over six round trips (ms)Base340.9Head62.7Bars: median of 5 runs. White lines: min–max. Lower is faster.

Linux Chromium · 1440×900 · dark · dev build · no CPU throttle

Long-name workloadBase 01c8e59f14Head f18f883260
Layout passes / round trip220.17 (220.00–241.33)20.00 (20.00–41.50)
Layout ms / round trip45.50 (34.56–49.03)21.22 (18.00–33.26)
Sampled fit ms / six round trips340.85 (284.90–401.30)62.75 (53.91–85.37)
Busy ms / round trip1807.83 (1710.95–2410.29)1486.76 (1307.93–2290.33)
Longest task ms813.00 (720.00–1048.00)604.00 (562.00–966.00)

Values are median (min–max), five runs of six round trips. Fitting is sampled CPU time, including layout called from the fit function. Busy time covers the whole app. Identical synthetic data on both commits.