**libevent removal** - Any previously installed applications depending on the `libevent` library in base will require recompilation, as this library is no longer supplied as standard.
-**VirtualBox, Virtual PC, and VMWare users** - Unless your virtual hard disk is 50G or larger, we recommend
-doing a UFS install and not the default HAMMER install. We also recommend installing from the CD ISO
-and not the DVD ISO.
+**VirtualBox, Virtual PC, and VMWare users** - Unless your virtual hard disk is 50G or larger, we recommend doing a UFS install and not the default HAMMER install. We also recommend installing from the CD ISO and not the GUI IMG. A more serious installation should use HAMMER with at least a 50G disk image and can install from the GUI IMG.
**Virtual PC users** - Virtual PC does not supply serial numbers for the virtual disks. The system may need to be manually directed in the boot loader if the disk identifier changes. (Hit ? in the boot loader for a list of available volumes.)
> ### Kernel changes
* dsched, an IO Scheduler framework and dsched_fq, a Fair Queuing I/O scheduler policy.
* Device Mapper imported from NetBSD.
-* stripe and crypt targets for the Device Mapper.
+* stripe and crypt targets for the Device Mapper (stripe is further enhanced as well).
* select(2), poll(2) and kqueue/kevent(2) implementations were unified on top of the existing kqueue implementation.
* Device polling API's and selrecord/selwakeup were dropped, in favor of kqueue's knote API, simplifying device implementation.
* LWKT tokens reworked to improve efficiency, especially in recursive scenarios.
* VM: Idle time page zeroing.
* Major update of pf from OpenBSD 3.5 to 4.2, keeping DragonFly specific additions (support for pickups and fairq).
* Network socket flags were made atomic.
-* Additional portions of the network stack were removed from under the MPLOCK.
+* Many minor bug fixes and improvements to HAMMER.
+* HAMMER now has a catastrophic recovery utility.
+* Additional major portions of the network stack were removed from under the MPLOCK.
* Major performance improvements to softcrypto on SMP systems.
* kern_udev - A framework to associate optional information with device nodes.
* initrd (initial ramdisk/malloc disk) support.