The results from the second test case we are sharing are from the 7-Zip compression benchmark, which is measuring the MIPS count and not at all dependent upon the file-system. As you can see, even in a CPU bound test, both of these systems had regressed horribly. Since February the regression introduced in the Linux 2.6.35 kernel is by far the most significant affecting compress-7zip. The MIPS count for the 64-bit Atom 330 dropped by more than 30% while the other setup dropped by nearly 40%.
With the multi-threaded PBZIP2 compression test, this Linux 2.6.35 kernel performance problem is astonishing! With the Atom Z530 setup the time needed to compress a 256MB sample file nearly doubled while the other setup increased by 50%.
In the CPU-bound FFmpeg video encoding test, the time to encode a sample NTSC video file increased by over 30%, but the other system has strangely been unaffected.