Vesper: Measuring Time-to-Interactivity for Web Pages
summary
Proposes a concrete interactivity metric called Ready Index and a rewiring tool Vesper that discovers which DOM nodes and JS heap variables must be loaded for above‑the‑fold functionality. Vesper uses heavy offline tracing (Scout logs) then lightweight logging to measure readiness with 4.5% and 1.9% overheads. Across 350 sites and varied RTTs, prior metrics misestimate time‑to‑interactivity by 24–64%; optimizing with Vesper and Polaris cuts median time‑to‑interactivity by ~29–32% and 83% of users prefer the interactivity‑optimized pages.
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chapters (9)
- 0:00Start
- 3:58Existing Metrics
- 9:26Measuring Ready Index (RI)
- 10:02Vesper: Overview
- 10:31Vesper: Phase 2
- 14:17Evaluation Outline
- 19:06User Study 2: Rendering
- 20:03Conclusion
- 22:41THE ADVANCED COMPUTING SYSTEMS ASSOCIATION
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