It has been four years since AMD magnificently presented this new open-source strategy, but the open-source driver stack does not reign supreme over the proprietary Catalyst driver. The level of performance is acceptable for most OpenGL workloads, but there are some exceptions -- for better and worse.
It is worth noting that AMD is not looking to achieve the same level of performance with their open-source driver as what is found with Catalyst. The 80~90% performance of Catalyst that we are commonly seeing for this older hardware is in line with what AMD's John Bridgman and others have been after. Additional performance can be squeezed out of the open-source code, but it is a matter of whether such investment is worthwhile. For newer Radeon GPUs, we are also still waiting for the stack to even reach 80% the speed of Catalyst.
Besides the performance, the open-source driver stack still needs to catch up with supporting modern revisions of OpenGL (i.e. OpenGL 3.0+), better power management, and other features being sought after by desktop Linux users.
Stay tuned for more Radeon Linux benchmarks to come next month in celebration of the open-source strategy anniversary and for the birthday of their new Linux driver. There may possibly be a Phoronix-sponsored open-source AMD anniversary party at XDC2011 Chicago as well, which is happening a week after the anniversary, but that's still being planned. Among the open-source AMD contributors (past and present) that should be here include Alex Deucher, Jerome Glisse, Luc Verhaegen, Matthias Hopf, and Egbert Eich. Unfortunately, it does not look like John Bridgman or AMD's most recent hires will be attending the X.Org Developers' Conference that I am the organizer of this year.
Until the next set of articles and benchmarks arrive, be sure to stop by the Phoronix Forums where the latest open-source AMD work is being discussed along with the valuable commentary of John Bridgman (the most prolific contributor to the forums) and other developers.