Hello WebKit-dev,

I’d like to request WebKit’s official position on scheduler.postTask(), an API for scheduling and controlling prioritized tasks. It is specified in [1] and further described in [2]. We’ve presented the API a few times to the WebPerf WG. One concern raised there by rniwa was the risk of priority inversions, which we’ve explored in [3].

We recently finished running an Origin Trial in Chrome. Airbnb, who we’ve been working closely with, experimented with using the API to improve their site’s performance, which they wrote about recently [4].

[1] Spec: https://wicg.github.io/scheduling-apis/
[2] Explainer: https://github.com/WICG/scheduling-apis/blob/main/explainers/prioritized-post-task.md
[3] Priority inversion exploration: https://github.com/WICG/scheduling-apis/blob/main/misc/priority-inversion.md
[4] Airbnb blog post: https://medium.com/airbnb-engineering/building-a-faster-web-experience-with-the-posttask-scheduler-276b83454e91

Additional Links:
 - Preliminary TAG review: https://github.com/w3ctag/design-reviews/issues/338
 - TAG Spec review (under review): https://github.com/w3ctag/design-reviews/issues/647
 - Chrome Status entry: https://www.chromestatus.com/feature/6031161734201344

Thank you,
Scott