The 2.10 release supports, thanks to updates of ACPI and APIC interrupt routing support, a much larger variety of hardware and multiprocessor systems than previous releases.
The Hammer Filesystem can now deduplicate volumes overnight in a batch process and during live operation. For estimation of space savings for existing data you can use this command:
# hammer dedup-simulate
The pf Packet Filter was updated to match OpenBSD's 4.4 version of pf where DragonFly BSD used pf from OpenBSD 4.2 before.
Gcc 4.4 is now used as the default system compiler. Oher BSDs use older gcc versions, so it's the first to take that step.
The bridging system has been rewritten. Multiple interfaces on a single system can be bound together transparently under a single virtual MAC address, and bandwidth aggregated to that new interface.
The MPLOCK (the primary lock, that when held ensures only a single cpu is operating within the kernel) has been removed from every area except the VM system. DragonFly is one of the few non-academic operating systems to use a primary sychronization mechanism that is not a blocking mutex.
DragonFly BSD now offers significant performance gains over previous releases, especially for machines using AHCI or implementing swapcache(8).