1072370 - Reduce the amount of copying happening with OMTC.

Status: RESOLVED WONTFIX

(Core :: Graphics: Layers, defect)

Description

[Nicolas Silva [:nical]]

When some pixels are to be presented to the compositor, if they haven't been allocated specifically for this (through a TextureClient), they need to be copied into a TextureClient. This is a wast of CPU and memory.

In the case of ImageLayers the typical symptom for running into this case is going through this branch: http://dxr.mozilla.org/mozilla-central/source/gfx/layers/client/ImageClient.cpp?from=ImageClient.cpp#293

We also do a full copy of every frame produced by non-SurfaceStream canvas2D.
(see http://dxr.mozilla.org/mozilla-central/source/gfx/layers/CopyableCanvasLayer.cpp )

Comment 1

[Nicolas Silva [:nical]]

The ImageLayer cases aren't happening a lot thanks to CairoImage already using TextureClient internally. Could make a difference on pages where we use RasterImage a lot (which doesn't use TextureClient, so is getting copied every time it is created or updated).