1566912 - Janky scrolling on mozilla.design/firefox caused by blob rendering

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P3)

Description

[Asif Youssuff]

Attachment: firefox-support.txt

Profile: https://perfht.ml/2XXAeym

STR: Load page, scroll up and down.

Slow Frame #01 Frame 126(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 24391 - Transaction start 3868.666436, main-thread time 2.606476, full paint time 24.261690, Skipped composites 0, Composite start 3933.978016, Resource upload time 23.731014, GPU cache upload time 36.388111, Render time 61.832683, Composite time 115.655901
Slow Frame #02 Frame 125(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 9474 - Transaction start 1.041506, main-thread time 1.339980, full paint time 18.964752, Skipped composites 0, Composite start 1518.102648, Resource upload time 25.306030, GPU cache upload time 0.209583, Render time 27.894613, Composite time 59.191100
Slow Frame #03 Frame 12(moz-extension://68e210f0-1a9a-424f-8cce-f3d9553a6567/popup.html) CONTENT_FRAME_TIME 3226 - Transaction start 0.229507, main-thread time 0.519109, full paint time 1.587451, Skipped composites 0, Composite start 534.019080, Resource upload time 0.000417, GPU cache upload time 0.054837, Render time 1.456981, Composite time 3.527409
Slow Frame #04 Frame 1(about:blank) CONTENT_FRAME_TIME 2244 - Transaction start 0.090559, main-thread time 0.155787, full paint time 4.265010, Skipped composites 0, Composite start 373.135013, Resource upload time 0.000000, GPU cache upload time 0.000000, Render time 0.000000, Composite time 0.000000
Slow Frame #05 Frame 128(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 2064 - Transaction start 22.231436, main-thread time 1.712831, full paint time 163.225836, Skipped composites 0, Composite start 195.773689, Resource upload time 13.281815, GPU cache upload time 0.243162, Render time 50.809301, Composite time 148.130809
Slow Frame #06 Frame 177(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 2009 - Transaction start 3.628585, main-thread time 1.883495, full paint time 125.125730, Skipped composites 0, Composite start 228.266874, Resource upload time 92.091419, GPU cache upload time 0.135266, Render time 94.094723, Composite time 101.891626
Slow Frame #07 Frame 129(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 1979 - Transaction start 5.338982, main-thread time 1.767947, full paint time 241.506292, Skipped composites 0, Composite start 267.897994, Resource upload time 0.000508, GPU cache upload time 0.136565, Render time 1.886521, Composite time 52.694511
Slow Frame #08 Frame 4(moz-extension://68e210f0-1a9a-424f-8cce-f3d9553a6567/popup.html) CONTENT_FRAME_TIME 1867 - Transaction start 0.144301, main-thread time 26.360033, full paint time 29.928795, Skipped composites 0, Composite start 128.610827, Resource upload time 0.000441, GPU cache upload time 0.000113, Render time 10.457144, Composite time 179.757327
Slow Frame #09 Frame 153(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 1864 - Transaction start 3.757071, main-thread time 2.625847, full paint time 75.745778, Skipped composites 0, Composite start 181.255921, Resource upload time 104.353607, GPU cache upload time 0.140811, Render time 107.498662, Composite time 123.615690
Slow Frame #10 Frame 152(https://mozilla.design/firefox/) CONTENT_FRAME_TIME 1734 - Transaction start 6.007269, main-thread time 3.649570, full paint time 52.504035, Skipped composites 0, Composite start 94.056085, Resource upload time 172.483197, GPU cache upload time 0.603140, Render time 175.356098, Composite time 188.733282

Comment 1

[Jeff Muizelaar [:jrmuizel]]

Attachment: A minimized version of the animation

There are more problems than just this on the page. But this is one to start with.

Comment 2

[Nicolas Silva [:nical]]

It looks like this one would benefit from optimizing empty tiles.

Comment 3

[Nicolas Silva [:nical]]

Not quite 60fps but this works well enough now and blobs don't show up in the profiles anymore thanks to Jeff's blob splitting patch.