Intel Sandy Bridge On Ubuntu 11.04 Is Still Troubling
When Intel released their "Sandy Bridge" processors in early January with next-generation graphics, the Linux support was widely criticized as although they had been working on the open-source Linux driver for nearly one year at that time, it wasn't a pleasurable "out of the box" experience and building open-source graphics drivers on Linux can be a real pain. With Ubuntu 11.04, which was released at the end of April, this "Natty Narwhal" release still largely misses the Sandy Bridge support train.
Following the failures of others to get Sandy Bridge graphics working properly under Linux, Intel supplied Phoronix with an Intel Core i5 2500K for my own set of Linux tests. Sure enough, the "out of the box" experience with distributions of the time (e.g. Ubuntu 10.10) was poor with 3D acceleration failing, but using the latest open-source code had worked. That is, after first battling an ASUS motherboard problem with the Linux driver.
When building the latest open-source Intel Linux driver graphics code of the time, OpenGL had worked and it was fast. That linked article provides a nice overview of the Intel Sandy Bridge Linux support situation as of this past February along with graphics benchmarks under Linux using the Linux 2.6.38 / Mesa 7.11-devel / xf86-video-intel 2.14 components. While the Sandy Bridge Linux graphics were functioning well, the initial driver code was slower than their Windows SNB driver.
In early March, though a simple patch dramatically improved the Linux driver's performance within the Mesa code-base for the yet-to-be-released Mesa 7.11. This patch increased the VS thread count to 60 for Intel "Gen 6" Sandy Bridge hardware. The performance became rather nice with Mesa 7.11-devel and Linux 2.6.38 and was only further enhanced in the Linux 2.6.39 kernel via the LLC caching patch-set. Where the latest code is at for the Linux kernel and Mesa is rather pleasurable for Intel Sandy Bridge owners using the integrated graphics, assuming you are able to build and install them.
In the case of Ubuntu 11.04, it's shipping with the Linux 2.6.38 kernel, but more importantly it's still shipping with the Mesa 7.10 series (the Mesa 7.10.2 bug-fix release) rather than a Mesa 7.11 development snapshot. While the "out of the box" Sandy Bridge experience with Ubuntu 11.04 "Natty Narwhal" is much better than where it was with Ubuntu 10.10 as kernel mode-setting is working smoothly, basic OpenGL is working, Compiz runs fine with the Unity desktop for a composited experience, etc, but it's not without various problems due to the slightly older code. All of the Phoronix tests of Intel Sandy Bridge focused around building the latest upstream code, so in this article we're seeing the real Ubuntu 11.04 "out of the box" Intel Sandy Bridge experience.