Following that earlier 4.9 Git benchmarking I set out to do a fairly large Linux kernel comparison on a Haswell system to go back three or so years worth of kernel releases. That big kernel comparison will be finished up and posted in the days ahead, but already from this Core i7 4790K Devil's Canyon system I am seeing some performance improvements with 4.9 Git to share over 4.7.0 and 4.8.0 stock kernels...
Here's a teaser of some of the data until having the big 3.x/4.x kernel comparison complete.
The vanilla kernel build has changed to the deadline I/O scheduler for possibly explaning a large part of the I/O performance difference. There have also been EXT4 fixes and other improvements as experienced on the i7-6800K, so will be running tests on more systems (and some fresh I/O scheduler comparison tests) to discover more in the days ahead. As shown below in some of the non-disk tests like FFTW, there were also performance improvements with 4.9, making it look like multiple improvements/changes could be at play.
Some of the LinuxBenchmarking.com daily kernel Git test systems have also seen some improvements with 4.9 code too, but unfortunately it's less easy to decipher there and still working on some more usability improvements with that constantly-growing massive data-set.
Wins outside of disk tests are also present.
This preliminary data via this OpenBenchmarking.org result file. Stay tuned for more results. For any specialized test/system benchmark requests, feedback, or to simply support this work, please consider becoming part of Phoronix Premium to access the site ad-free, single-page article viewing, and priority honoring of any feedback / test requests.