
Previously we tracked the maximum scroll offset in a viewport to ignore counterscroll shifts, but it failed when - There were multiple scrollers scroll at the same time. Tested by external/wpt/layout-instability/shift-with-counterscroll-2.html. - An invisible shift was countered by both scroll and transform, e.g. move layout location by 100px, scroll by -50px, and transform by -50px. Tested by external/wpt/layout-instability/shift-with-counter-scroll-and-transform.html Now let PaintPropertyTreeBuilder track scroll delta, and pass the delta to LayoutShiftTracker. Bug: 1182213 Change-Id: I18366ff7bc0e96374a954bee1c1600b582681dd8 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2741240 Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org> Reviewed-by: Chris Harrelson <chrishtr@chromium.org> Reviewed-by: Steve Kobes <skobes@chromium.org> Cr-Commit-Position: refs/heads/master@{#861702}
Chrome Speed
Contact information
- Contact: speed@chromium.org
- Escalation:
- benhenry@chromium.org (TPM)
- File a bug: template
- Regression postmortem: template
User Docs
- How does Chrome measure performance?
- My CL caused a performance regression! What do I do?
- I want Chrome to have better performance
- Perf sheriffing documentation
- I want to add tests or platforms to the perf waterfall
Core Teams and Work
- Speed domain area experts: These mailing lists and bug triage rotations provide expertise into specific domain areas of Speed: memory, power, loading, responsiveness, binary size, data usage, and browser UI.
- Chrome Speed Operations: provides the
benchmarks, infrastructure, and releasing oversight to track regressions.
- Benchmark-specific discussion: benchmarking-dev@chromium.org
- Performance dashboard, bisect, try jobs: speed-services-dev@chromium.org
- Chrome Speed Metrics: provides a set of high-quality metrics that represent real-world user experience, and exposes these metrics to both Chrome and Web Developers.
- General discussion: speed-metrics-dev@chromium.org
- The actual metrics: speed launch metrics survey.