Earlier this week AMD released the Catalyst 10.6 driver that on the Linux side of the table had finally made use by default of their new 2D acceleration architecture, offered official support for Red Hat Enterprise Linux 5.5, and formalized their OpenGL 3.3/4.0 support. Since the release of the Catalyst 10.6 Linux driver, we have been running a new set of tests on their new ATI 2D acceleration architecture, but the results are not what you may expect when compared to the open-source ATI Linux driver.
Back in February we reported that the Linux Catalyst driver is using Direct2D code for their new 2D acceleration paths beginning with the Catalyst 10.2 driver release. Up until now, this new 2D acceleration architecture has not been officially communicated by AMD and would not be used by default unless enabling it via an AMDPCSDB (AMD Persistent Configuration Store Data-Base) key called Direct2DAccel. Those testing out this new 2D acceleration for the Catalyst Linux driver experienced some success but others encountered various obstacles and problems with their 2D rendering. Four months later AMD is now satisfied with this new acceleration architecture and it is flipped on by default with Catalyst 10.6 and later. When using this new architecture there should be an "ATI 2D Acceleration Architecture enabled" line within the /var/log/Xorg.0.log file rather than "Using XFree86 Acceleration Architecture (XAA)."
There have been some positive reports based upon the vast feedback in these two forum threads: ATI Catalyst 10.6 Released and AMD Catalyst 10.6 For Linux Brings Changes while others are experiencing problems like the driver not even working. There has also been some ecstatic comments like "Direct2D is enabled by default and its bloody fast!" and "I must say that this is the first version of fglrx that's pleasantly surprised me. Good work, ATI/AMD."
Our testing of the AMD Catalyst 10.6 driver on Linux and its pre-releases have been rather favorable in regards to the 2D experience. Tasks like minimizing windows and scrolling feels more fluid and faster, which actually puts the feeling closer to that of the open-source ATI Radeon driver stack on Linux. However, our synthetic 2D benchmarks are actually showing a performance drop in a few quantitative tests. For the numbers that are being reported we compared the Catalyst 10.4 driver found within the Ubuntu Lucid repository to Catalyst 10.6 with its new ATI 2D Acceleration Architecture and then the open-source ATI Radeon DRI2+KMS driver stack found by default in Ubuntu 10.04 LTS.
We once again used the Intel Core i3 530 system clocked at 3.32GHz with an ECS H55H-M motherboard, 2GB of system memory, a 64GB OCZ Vertex SSD, and an ATI Radeon HD 4650 (RV730PRO) graphics card. Ubuntu 10.04 LTS x86_64 was used with the Linux 2.6.32 kernel, GNOME 2.30.0 desktop, and X.Org Server 1.7.6. The open-source ATI driver stack consists of the DRM that was back-ported to the stock Lucid kernel from the Linux 2.6.33 kernel, xf86-video-ati 6.13.0, and Mesa 7.7. The Catalyst 10.4 package has the fglrx driver at version 8.72.11 while with Catalyst 10.6 it is fglrx 8.74.4. The 2D benchmarks ran included QGears2, GtkPerf, Render Bench, and x11perf. The Phoronix Test Suite facilitated this testing.