With IE9, developers have a fully-hardware accelerated display pipeline that runs from their markup to the screen. Based on their blog posts, the hardware-accelerated implementations of other browsers generally accelerate one phase or the other, but not yet both. Delivering full hardware acceleration, on by default, is an architectural undertaking. When there is a desire to run across multiple platforms, developers introduce abstraction layers and inevitably make tradeoffs which ultimately impact performance and reduce the ability of a browser to achieve ‘native’ performance. Getting the full value of the GPU is extremely challenging and writing to intermediate layers and libraries instead of an operating system’s native support makes it even harder. Windows’ DirectX long legacy of powering of the most intensive 3D games has made DirectX the highest performance GPU-based rendering system available.
When you run other browsers that support hardware acceleration, you’ll notice that the performance on some of the examples from the IE Test Drive site is comparable to IE9 yet performance on other examples isn’t. The differences reflect the gap between full and partial hardware acceleration. As IE supports new, emerging Web standards, those implementations will also be fully hardware accelerated.
Hardware acceleration of HTML5 video is a great example. At MIX10, we showed the advantage of using hardware for video. In March, IE9 played two HD-encoded, 720p videos on a netbook using very little of the CPU while another browser maxed out the CPU while dropping frames playing only one of the videos. Because of full hardware acceleration of the entire pipeline, you experience great performance playing these videos while moving them around the page and styling and compositing them with opacity, using web standard markup.
