The disk read and write performance was slightly faster using the newest Linux 2.6.28 kernel as measured by IOzone.
With the Sunflow Rendering System its performance had improved in the 2.6.27 and 2.6.28 kernel releases on our Intel Core 2 Duo system.
There really isn't much to say from these results with this Intel Core 2 system. In a few tests we had witnessed better performance with the latest Linux 2.6.28 kernel, but as a whole the performance was flat-lined between the 2.6.25 and 2.6.28 kernels -- at least there are no performance regressions to note. We will be back with more benchmarks from other hardware, extended tests, and more kernel releases in the future. If you would like to run your own tests, check out the Phoronix Test Suite.
To compare your system and kernel to our results, run phoronix-test-suite benchmark phoronix-29631-5011-23280.