Contact emailsshase...@chromium.org Explainer https://github.com/WICG/scheduling-apis/blob/main/explainers/yield-and-continuation.md
SpecificationNone Summary Provides a method for yielding control to the browser, which can be used to break up long tasks. Awaiting the promise returned by scheduler.yield() causes the current task to yield, continuing in a new browser task. This can be used to improve responsiveness issues caused by long tasks. Continuations are prioritized to mitigate performance problems of existing alternatives. Blink componentBlink>Scheduling>APIs <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EScheduling%3EAPIs> TAG reviewEarly design review: https://github.com/w3ctag/design-reviews/issues/827 TAG review statusPending Risks Interoperability and Compatibility This is a new feature and will not change existing event loop task scheduling, so the main risk is that other browsers might not implement the feature. There is an interop challenge, however, that comes with prioritization: we want to be specific enough to provide developers guarantees and interoperable implementations, but provide enough scheduling flexibility for UAs (like the HTML specification does with task sources/task queues), which we'll keep in mind while drafting the spec (see also https://github.com/WICG/scheduling-apis/issues/67). *Gecko*: No signal *WebKit*: No signal *Web developers*: No signals *Other signals*: Ergonomics The default use (inserting yield points in long tasks) should enable Chrome to maintain better performance (responsiveness). There is a risk of continuations starving other work, but there are reasonable mitigations, e.g. bounding total of prioritized continuations (see also https://github.com/WICG/scheduling-apis/blob/main/explainers/yield-and-continuation.md#preventing-task-starvation-by-continuations). This is something we'll be looking for in origin trial feedback. Activation The feature would benefit from a polyfill so that tasks still yield in the case the feature is unavailable. The behavior can be approximated by awaiting `scheduler.postTask()` or wrapping `setTimeout(0)` in a promise. The signal inheritance bit [1], however, would need transpilation support to propagate the current signal across async (Promise) boundaries. But developers can alternatively pass the appropriate priority/signal if necessary on browsers that don't support the feature. [1] https://github.com/WICG/scheduling-apis/blob/main/explainers/yield-and-continuation.md#priority--abort-propagation-behavior Security See https://github.com/WICG/scheduling-apis/blob/main/explainers/yield-and-continuation.md#self-review-questionnaire-security-and-privacy WebView application risks Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications? None Goals for experimentation Ongoing technical constraints None Debuggability This has basic new-API devtools support. We plan to work with the devtools team to see if we can integrate continuations into the performance panel in some way. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?Yes Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> ?Yes ( https://wpt.fyi/results/scheduler/tentative/yield?label=experimental&label=master&aligned ) DevTrial instructions https://github.com/WICG/scheduling-apis/blob/main/implementation-status.md Flag name--enable-blink-features=SchedulerYield Requires code in //chrome?False Tracking bughttps://bugs.chromium.org/p/chromium/issues/detail?id=979020 Estimated milestones DevTrial on desktop 113 DevTrial on Android 113 Link to entry on the Chrome Platform Status https://chromestatus.com/feature/6266249336586240 Links to previous Intent discussionsIntent to prototype: https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAKXGoJ1SBQP-ABM3%2BsDtKzUZiPoSCWqW2mLOjMrUfFBx4TomSw%40mail.gmail.com 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/CAKXGoJ1EFWi9YY1aAHbK7abcMvUzOVG9eqJe3mdhxXJp_MwUrg%40mail.gmail.com.
