Last week I delivered benchmarks showing how Ubuntu 12.04 is ARM-ing up for better performance with ARM-based hardware and detailed some of the plans Canonical has for this architecture going forward. While those benchmarks last week illustrated some significant performance improvements with the Ubuntu 12.04 stack -- in large part due to the switch to hard floating-point support -- the gains are not over. In fact, there are already some striking improvements if using the Texas Instruments OMAP4460 SoC as found on the PandaBoard ES.
The Ubuntu 12.04 results last week benefited from the ARM hard-float binaries in the Precise repository, but after publishing the results and communicating with Texas Instruments, it turned out that the Linux 3.2 kernel build had a problem for the OMAP4460. The OMAP4460 SoC was not fully supported under Ubuntu 11.10's Linux 3.0 kernel but is with the Linux 3.2 kernel. However, the Ubuntu kernel maintainers did not have the OMAP4460 cpufreq support enabled within their 3.2 kernel build in Precise as of last week. That issue was quickly resolved with a new kernel build being uploaded for Ubuntu's ARMv7 OMAP4 support.
With the cpufreq support enabled, the dual-core Cortex-A9 can now run as low as 300MHz or ramp up to its highest 1.2GHz frequency stepping when needed. Without the cpufreq support, the SoC is just stuck running at around 1.0GHz. With this support finally enabled for Ubuntu Linux, there is some immediate performance boosts for the PandaBoard ES.
This article adds in the results from Ubuntu 12.04 LTS as of 26 January (when the cpufreq OMAP4460 configuration was fixed) compared to the Ubuntu 12.04 LTS results from just two days prior and to the Ubuntu 11.10 reference results.