For those curious about performance differences between the current Debian 7.3 "Wheezy" stable release and the upcoming but currently unstable Debian 8.0 "Jessie", here are some performance benchmarks comparing Debian's stable and testing releases on the same hardware. Making things more interesting, Ubuntu 14.04 LTS in its current development form was also tossed into the mix.
All of this Debian and Ubuntu testing happened from a CompuLab Intense-PC with Intel Core i7 "Ivy Bridge" processor. Debian 7.3, Debian Jessie Testing, and Ubuntu 14.04 were left in their stock forms with default settings. Ubuntu 14.04 is currently riding on the Linux 3.13 kernel with GCC 4.8.2 and Mesa 10.0.1 while Debian 7.3 uses the Linux 3.2 kernel with GCC 4.7 and Mesa 8.0.5. Lastly, Debian Jessie is using right now the Linux 3.12 kernel, GCC 4.8.2, and Mesa 9.2.2. The CPU was also clocked the same during testing but on the system table the difference is due to the Intel P-State driver reporting the Turbo Frequency on Debian Jessie while the ACPI CPUfreq driver is used right now on Ubuntu 14.04 and Debian Stable for this Core i7 IVB CPU.
This Ubuntu and Debian Linux benchmarking was handled in a fully automated manner using the open-source Phoronix Test Suite benchmarking platform. The testing is very straight forward so let's get straight to these new performance metrics. If you are curious about the performance between Debian GNU/Linux and Debian GNU/kFreeBSD, check out last month's Debian benchmarks.