DragonFly BSD 2.10.1 is a BSD operating system originally forked from FreeBSD 4 series. This release sports significant compatibility and performance improvements and many new features. Big-ticket items: this release supports a much larger variety of hardware and multiprocessor systems than previous releases, thanks to updates of ACPI and APIC and ACPI interrupt routing support; Hammer volumes can now deduplicate volumes overnight in a batch process and during live operation; Packet Filter (pf) was updated to a version based upon OpenBSD 4.4; DragonFly now uses GCC 4.4 as the default system compiler, and is the first BSD to take that step; significant performance gains over previous releases.
About DragonFly BSD
DragonFly is an operating system and environment designed to be the logical continuation of the FreeBSD-4.x OS series. These operating systems belong in the same class as Linux in that they are based on UNIX ideals and APIs. DragonFly is a fork in the path, so to speak, giving the BSD base an opportunity to grow in an entirely new direction from the one taken in the FreeBSD-5 series.