Sam Spilsbury shared today via his blog about Compiz performance improvements and an experimental Personal Package Archive (PPA) being available on Launchpad.
The latest round of improvements for this compositing window manager used by Ubuntu include:
- Support for using the GLX_EXT_buffer_age extension. The only Linux graphics driver currently implementing this extension is the brand new NVIDIA 313.09 beta driver but support for this extension will soon land in Mesa/Gallium3D for the common open-source drivers when using a modern kernel for the latest DRM. The GLX_EXT_buffer_age extension will allow for tear-free rendering with the same level of performance as carrying out incremental updates to the back-buffer. Spilsbury says that in his simple tests of the buffer-age extension, there's been a 200 FPS increase.
- Support for the GL_EXT_blit_framebuffer extension. The GL_EXT_blit_framebuffer OpenGL extension can be used to enable fast frame-buffer copies when rendering with post-processing.
- A fix to avoid flooding the X.Org Server with ConfigureWindow requests upon window movement. This addresses a performance bottleneck on NVIDIA in certain situations.
- A window stacking bug-fix.
Spilsbury says in his blog post, "There should be an across-the-board framerate increase when using this PPA."
The PPA for these major Compiz performance enhancements are found from ppa:smspillaz/compiz-experimental. The new window manager packages are at version 0.9.9-1-experimental1+bzr3528-201212131812 and there's Debian builds available for Ubuntu 12.04 (Precise), 12.10 (Quantal), and 13.04 (Raring).
As I already shared on Twitter, coming out soon (likely tomorrow) will be some new OpenGL performance benchmarks with the experimental Compiz package to check out the performance improvements. The initial testing will likely be limited to a NVIDIA 313.09 setup with the GLX_EXT_buffer_age support while more thorough multi-desktop testing will be done as Ubuntu 13.04 nears and the next Compiz release stabilizes.