handling impact of isInputPending on long tasks metrics? · GoogleChrome/lighthouse#11747

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P2good first issuemetrics-cwv

説明

navigator.scheduling.isInputPending is shipping by default in current Chrome stable (m87). Without user input, any page using isInputPending has a strong reason to believe yielding during long tasks won't improve user experience so it could keep on chugging instead.

This may have a large impact on any metric looking at long tasks (TBT, TTI) compared to what a real user would experience when loading the same page.

There was a discussion in the WICG about how it should interact with the Long Tasks API and warnings against long tasks, as well if there should be a way to tell if isInputPending was called during a particular long task: https://github.com/WICG/is-input-pending/issues/37
Chrome status entry

コントリビューターガイド

技術スタック: javascript
領域: performanceobservability
Issue 種別: research
難度: 4
推定時間: over 1 week
活動状況: stale
明確さ: mostly clear
前提条件: Long Tasks APInavigator.scheduling.isInputPendingTBT metricTTI metric
初心者向け度: 20
調査方針: Investigate the WICG discussion at https://github.com/WICG/is input pending/issues/37 to understand proposed interactions with Long Tasks API. Review Chrome status entry for implementation details. Assess impact on Lighthouse's TBT and TTI audits by considering how isInputPending affects long task duration. Propose whether to incorporate isInputPending detection into existing metrics or add a new audit.