On Platform GTK the revision r170529 <http://trac.webkit.org/r170529> caused a performance regression around ~10% on the test Animation/balls. You can check the performance graph at https://perf.webkit.org/#mode=charts&chartList=%5B%5B%22gtk%22%2C%22Animation%2Fballs%3AFrameRate%22%5D%5D&days=44 (we identified r170529 as the commit causing the regression on the interval r170529-r170540 after a manual bisect) The overall performance is still very poor in this test: Around 5 FPS. Comparing with the other ports: EFL gets around ~10FPS, and MAC ports around ~30FPS. Zan Dobersek (CC'ed) identified an issue with the GTK port and this test: DrawingArea is not entering the accelerated compositing codepaths. He tried to force-enable the accelerated compositing path, and the animations in the benchmark became much more fluent, but the test is still only reporting ~10FPS. Then he tried to revert r170529 and the FPS jumped to 20FPS. So, it seems that r170529 is causing a significative performance regression on this test. You can run the test as follows: Tools/Scripts/run-perf-tests --release -2 Animation/balls.html If you want to see the animation: USE_NATIVE_XDISPLAY=1 Tools/Scripts/run-perf-tests --release -2 Animation/balls.html
BTW, the test is self-contained. You can run it in any browser by opening: http://trac.webkit.org/export/171143/trunk/PerformanceTests/Animation/balls.html or file://${path-to-webkit}/PerformanceTests/Animation/balls.html
See https://bugs.webkit.org/show_bug.cgi?id=134109#c8.
Created attachment 235283 [details] Patch
Comment on attachment 235283 [details] Patch Clearing flags on attachment: 235283 Committed r171343: <http://trac.webkit.org/changeset/171343>
All reviewed patches have been landed. Closing bug.