The in-depth ZFS On Linux comparison using the new out-of-tree kernel module will happen on multiple disks and compared against EXT4, Btrfs, XFS, and friends. In this article are just some quick single SSD-backed results for a couple of tests and just compared to EXT4. Benchmarking happened from an updated Fedora 18 installation. The more thorough testing will come once all of the benchmarking has finished; today's results are just from a Lenovo ThinkPad W510 with an Intel SSD.
The benchmark results in full along with other software/hardware information from this Fedora 18 ZFS vs. EXT4 benchmarking can be found inside 1304170-UT-ZFSONLINU78.
With FS-Mark, the widely-used EXT4 file-system beats this native ZFS Linux implementation by a wide margin.
EXT4 is running about three times faster than a stock ZFS file-system from Fedora Linux.
Until the more thorough testing is complete, from last summer are some ZFS Linux benchmark results when using Ubuntu 12.04 LTS.