In January of this year was our first time benchmarking Debian GNU/kFreeBSD when it was using the FreeBSD 7.2 kernel. With that initial testing, in 18 of our 27 benchmarks Debian GNU/Linux was still faster than Debian GNU/kFreeBSD. We delivered a much larger comparison a week later when comparing the Debian variant to Fedora, FreeBSD 7.2/8.0, OpenBSD, and OpenSolaris. Debian GNU/kFreeBSD performed about average.
Our most recent benchmarks though of Debian GNU/Linux and Debian GNU/kFreeBSD were from this July where we looked at the Debian GNU/kFreeBSD performance using the FreeBSD 7.3 kernel, which was the default at the time, as well as when installing the FreeBSD 8.0 kernel from the kFreeBSD ports repository, which was available as a Debian package but not yet used by default. From that article:
Depending upon your local hardware configuration and the software that is relevant to you, the outcome as to what operating system is the fastest between Debian GNU/Linux, Debian GNU/kFreeBSD, and FreeBSD may vary. However, with these tests today on the two different Lenovo notebooks and testing both the 7.3 and 8.0 kernels from FreeBSD, the overall winner is Debian GNU/Linux. Debian GNU/Linux won the most tests in our original Debian GNU/kFreeBSD benchmarking and it continues to be that way still when looking at the default configuration.
This though is not to say that FreeBSD is a loser in terms of computing performance against Linux, but FreeBSD did possess a stronger advantage with tests like C-Ray and some I/O operations. FreeBSD and the other *BSDs also have their own set of features and focus that distinguish them from Linux in other ways besides the quantitative performance.
Debian GNU/kFreeBSD though has continued advancing since that point. When trying out the latest daily installer image of Debian GNU/kFreeBSD this week, there is not only the FreeBSD 8.1 kernel available, but it's now used by default. This Debian port is no longer using a Debian 7.x kernel by default but it's moved up to match the latest upstream FreeBSD stable release that's available.
Not only is Debian GNU/kFreeBSD more exciting for its new default kernel, but now it has ZFS file-system support too. Added to the kFreeBSD repository recently was a zfsutils package that provides the support for using and setting up ZFS file-systems.
Unfortunately though the Debian installer doesn't yet have support for installing to ZFS file-systems so for now your root file-system is basically limited to UFS. As of right now the ZFS pool version in use by this Debian non-Linux variant is Zpool 14, which is quite old. There isn't de-duplication support in there or the many other features found in revisions since then. As of earlier this month, upstream FreeBSD is now up to Zpool 28 to provide support for data de-duplication, triple parity RAIDZ (RAIDZ3), ZFS DIFF, Zpool Split, snapshot holds, forced Zpool imports, and the ability to import a pool in a read-only mode. Zpool 14 is even older than the current Linux ZFS-FUSE implementation (at Zpool 23) or the native ZFS module for Linux that is based upon Zpool 18.
Needless to say though, there will be new Debian GNU/Linux vs. Debian GNU/kFreeBSD benchmarks being published atop this FreeBSD 8.1 kernel in the coming weeks while away at Oktoberfest.