1410851 - MazeSolver suddenly extremely slow with WebRender

Status: RESOLVED WORKSFORME

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

Description

[niels.breuker]

Attachment: MazeSolverResultsFromAFewWeeksAgo.PNG

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:58.0) Gecko/20100101 Firefox/58.0
Build ID: 20171022220103

Steps to reproduce:

I tested WebRender on MazeSolver a few weeks ago and again today.

To try this yourself: 
1. Enable WebRender on Nightly with gfx.webrender.enabled, gfx.webrendest.enabled and gfx.webrender.blob-images set to true.
2. Go to https://testdrive-archive.azurewebsites.net/Performance/MazeSolver/Default.html
3. Open console and call 'changeMazeSize(51)'
4. Press start

The reason I change the size to 51 is because it's a pretty big maze and the browser has to go through almost everything in order to go to the end.


Actual results:

WebRender was incredibly slow suddenly


Expected results:

I expected the results to be similar or better than a few weeks ago.

WebRender used to be extremely fast on MazeSolver. A maze with the size of 51 was done in 25 seconds. No other engine could match that.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Can you use mozregression to track down a regression range?

Comment 2

[Milan Sreckovic [:milan] (needinfo for best results)]

How's this related to bug 1395184?

Comment 3

[Tom Levels]

Is this bug still valid? I just ran the test with webrender and it is faster than the current release version.

Comment 4

[niels.breuker]

It's much faster again, but it's still not at the level it was a few months ago. Currently a maze with the size of 51 is done in 48 seconds with WebRender on while a few months back it was done in 25 seconds. https://bug1410851.bmoattachments.org/attachment.cgi?id=8921020

Comment 5

[niels.breuker]

MazeSolver on my integrated GPU (Intel HD 630) is equally fast with my discrete GPU (NVIDIA GeForce 960M), so I doubt the bottleneck is in GPU side of WebRender.

Comment 6

[u480271]

A lot of time is spent in Retained Display List update and serializing WR commands on this test.

Comment 7

[Glenn Watson [:gw]]

Seems to run well on the couple machines I tested on recently.