I'm thinking of a few Phoronix benchmarks I've seen through the years. I'm not going to pretend like these benchmarks are the be all and end all, but I do think it (at the very minimum) compares run-times for common tasks.

https://www.phoronix.com/scan.php?page=article&item=comet-la...

In general, Linux comes out on top, FreeBSD follows, and Dragonfly takes third place. In some instances, Dragonfly beats out FreeBSD, but only just. The overall mean is that Dragonfly is only sightly worse than FreeBSD.

Again, not advocating for using phoronix benchmarks like it proves anything, but I think these results make sense.