686634 - Rendering a table with rounded corners is very slow with hardware acceleration

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect)

Description

[Luke Usherwood]

Attachment: SlowTables_HardwareAccel.zip

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0) Gecko/20100101 Firefox/7.0
Build ID: 20110908135051

Steps to reproduce:

A particular page containing a table with lots of cells performs very poorly when hardware acceleration is enabled. Scrolling by one page takes on the order of 400ms. Other actions have a similar delay: opening it, switching tabs; and when resizing the window it updates ~twice per second.

Without hardware acceleration there are no such delays, and it works fluidly.  My "from the armchair" hunch would be the rounded corners used in this table.

During these rendering 'glitches' firefox.exe doesn't show a considerable CPU usage. E.g. when resizing the window it averages about 30% of one CPU. (Hinting at graphics-memory delays or frequent locking??)

Reproduced in Firefox 4 through to most recent 7-Beta.

GRAPHICS (about:support):

Adapter Description: NVIDIA GeForce GTX 260
Vendor ID: 10de
Device ID: 05e2
Adapter RAM: 896
Adapter Drivers: nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2umDriver 
Version: 8.17.12.7533
Driver Date: 5-20-2011
Direct2D Enabled: true
DirectWrite Enabled: true (6.1.7601.17563)
GPU Accelerated Windows: 2/2 Direct3D 10

Comment 2

[j.j.]

Attachment: Reporter's testcase

Comment 3

[Benoit Girard (:BenWa)]

This is also slow on Mac

Comment 4

[Gregory Pappas [:gregp]]

Unable to reproduce in recent versions.