Contact emailsnrosent...@chromium.org Explainer https://github.com/w3c/longtasks/blob/loaf-explainer/loaf-explainer.md
Specification See https://github.com/w3c/longtasks/issues/103 and explainer Summary Revamp long tasks: - Measure long frames, from beginning of task until end-of-rendering or noop, as it's a more robust and representative unit of measurement than a "task". - Add attribution/breakdown: style & layout, script details. Blink componentBlink>PerformanceAPIs <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EPerformanceAPIs> Motivation Long tasks, shipped in Chrome 58, are marketed as the way to diagnose responsiveness/jank issues such as long INP. However, in the years since we've shipped them we found that they are lacking: 1. They don't contain the rendering phase, which means a lot of what goes into blocking interactivity is not counted 2. Long tasks are missing details about what made the task long 3. UI events are not specified nor implemented in terms of tasks, causing confusion. 4. Internal changes to how we deal with tasks in Chrome change the meaning of a "task" too often. The revamp: - Counting frames instead of tasks: from the beginning of the task until one of the following occurred: (1) the frame has been rendered (could be more than one task) 2) the task is complete and there are no changes (a classic long task without visual updates). - Add information about how long it took to style&layout, as well as a breakdown of long-running same-frame top-level scripts, plus additional information that can help diagnose long main-thread blocking periods. Initial public proposalhttps://github.com/w3c/longtasks/issues/103 TAG review TAG review statusPending RisksIt's still early, we need to see that we don't expose too much info here, either by bombarding with data or with privacy-sensitive data. Will review this once we assess the usefulness and feasibility. Interoperability and Compatibility Too early *WebView application risks* N/A Debuggability Concepts and naming have to align with DevTools timeline concepts and naming. Conversation about this has begun. Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> ?Not yet! Flag nameLongAnimationFrameTiming Requires code in //chrome?False Tracking bughttps://bugs.chromium.org/p/chromium/issues/detail?id=1392685 Estimated milestones No milestones specified Link to entry on the Chrome Platform Status https://chromestatus.com/feature/6118675067699200 This intent message was generated by Chrome Platform Status <https://chromestatus.com/>. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to blink-dev+unsubscr...@chromium.org. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAJn%3DMYbX%3DEOAwkEvDQY9Ja1trSXLFtM1XNsuw1Lr2QR88%2BTnqw%40mail.gmail.com.
