598936 - [D2D] Performance thewildernessdowntown.com significantly worse than on GDI

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Bas Schouten (:bas.schouten)]

The interactive video on thewildernessdowntown.com performs significantly better with GDI than with Direct2D. This means something is wrong.

Comment 1

[Bas Schouten (:bas.schouten)]

XPerf seems to indicate a lot of time being spent in nvlddmkm.sys. And CPU usage suggests we spend a lot of time blocking, presumably waiting on the GPU. What this demo does to weigh so heavily on the GPU I do not yet have any idea.

Comment 2

[Bas Schouten (:bas.schouten)]

We spend a very large amount of time in the Driver creating textures. These texture allocations are coming from Brush creation when doing a CreateBitmap. Trying to figure out what's causing this.

Comment 3

[Bas Schouten (:bas.schouten)]

So this time is spent creating the temporary surface in order to support EXTEND_NONE. EXTEND_NONE causes us to create a temporary bitmap with a one pixel transparent frame so we can then use CLAMP in D2D. This also seems to be frequently called by our border rendering code! Interestingly enough.

We should probably see if we can prevent us using EXTEND_NONE here and there. But I should also be able to optimize a lot of these cases in a fairly straightforward manner. Investigating.

Comment 4

[Bas Schouten (:bas.schouten)]

I've got patches which speed the demo up to being silky smooth on my machine. I will be putting them up on bug 599118 soon. These patches should also improve border drawing performance!