animations/no-style-recalc-during-accelerated-animation.html Is a constant text failure on iOS ToT and since 253549@main. HISTORY: https://results.webkit.org/?suite=layout-tests&test=animations/no-style-recalc-during-accelerated-animation.html DIFF: @@ -1,2 +1,2 @@ Got iteration event. -PASS: saw five or fewer style recalcs during the animation. +FAIL: saw 8 style recalcs during the animation, should only see five.
<rdar://problem/98894287>
DIFF URL: https://build.webkit.org/results/Apple-iOS-15-Simulator-Release-WK2-Tests/253549@main%20(4145)/animations/no-style-recalc-during-accelerated-animation-pretty-diff.html
This issue can be bisected to 253549@main using command: run-webkit-tests --ios-simulator --iterations=2 animations/no-style-recalc-during-accelerated-animation.html
Test gardening commit 253601@main (886100c335f4): <https://commits.webkit.org/253601@main> Reviewed commits have been landed. Closing PR #3481 and removing active labels.
animations/steps-transform-rendering-updates.html Is a constant text failure on iOS ToT with the same regression point of 253549@main. However, with a different DIFF. They both appear to be related. HISTORY: https://results.webkit.org/?suite=layout-tests&suite=layout-tests&test=animations%2Fsteps-transform-rendering-updates.html&test=animations%2Fno-style-recalc-during-accelerated-animation.html DIFF: @@ -1,5 +1,5 @@ PASS count is 0 -PASS count < 7 is true +FAIL count < 7 should be true. Was false. PASS successfullyParsed is true TEST COMPLETE
Test gardening commit 253602@main (7199d3824d94): <https://commits.webkit.org/253602@main> Reviewed commits have been landed. Closing PR #3482 and removing active labels.
The commit message claims that a few more rendering updates "should be benign". Not sure if the count is flaky now, or what the impact on power use is though.
I've been investigating the causes of the extra updates on iOS; haven't nailed it down yet, but it's benign (a few more per animation, not the "update every frame" that the test was designed to detect).
After lots of debugging, I think the iOS difference is due to differences in timer slop, and how we drive rendering updates with UI-side compositing. I did file bug 244276, and I'll adjust the test to call `setSpeculativeTilingDelayDisabledForTesting(true)` to make sure that doesn't introduce flakiness.
Pull request: https://github.com/WebKit/WebKit/pull/3482
Fixed via https://github.com/WebKit/WebKit/pull/3602