1306052 - Maze renderer is slower than Chromium

Status: RESOLVED DUPLICATE of bug 1409047

(Core :: Layout, defect, P3)

Description

[Zéfling]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0
Build ID: 20160927030200

Steps to reproduce:

Rendering Firefox is a bit slow compared to Chromium on Linux with:
http://sinz.org/Maze/table.html


Actual results:

Maze Complete   (Table)   [Firefox 52]
Maze size: 121 x 92 (11132 tiles)
238 	ms in JavaScript 	0.021 	ms/tile
114903 	ms not in JavaScript 	10.321 	ms/tile
115141 	ms total time 	10.343 	ms/tile
96.68 	tiles per second 	11 	tiles/step

Maze Complete   (Table)   [Chrome 53]
Maze size: 121 x 92 (11132 tiles)
129	ms in JavaScript	0.011	ms/tile
23464	ms not in JavaScript	2.107	ms/tile
23593	ms total time	2.119	ms/tile
471.83	tiles per second	11	tiles/step

With this example is almost 4 times slower.

With a maze greater the difference is worse.


Expected results:

Make the render faster.

Comment 1

[Markus Stange [:mstange]]

We spend a surprising amount of time in GetDisplayPortFromMarginsData, about 25% in my profile. Almost half of that is in ScrollFrameHelper::GetScrolledRect, which got a lot more complex in bug 1012752. The rest seems to be general display list building + layer building.

https://cleopatra.io/#report=3fcce1eb378196abf41d1185b6c30467776c8e5c&filter=%5B%7B%22type%22%3A%22RangeSampleFilter%22,%22start%22%3A18489767,%22end%22%3A18492854%7D%5D&selection=0,4096,4097,4098,4099,3818,4100,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,4218,4219,4220,4221,94,95,96,97,98,99,100,101,102,103,105,117,118,119,120,121

Comment 2

[Gregory Pappas [:gregp]]

Still a bit slower than Chrome in this demo.
https://share.firefox.dev/3XndcjV