This page will document changes that will be included in FreeBSD 9, including those that might end up being committed to earlier branches. In other words, it describes differences between 8.0 and 9.0, no matter what happens to the versions in between.

For information on the currently released 8-STABLE branch see What's cooking for FreeBSD 8 page.

Some of the more important low-level changes can be seen in the future release's UPDATING file.

Also useful are the quarterly Status Reports:

Everyone is encouraged to download a snapshot CD image and try all the new features (as well as the old ones). Developers are very interested in bug reports. Note that FreeBSD 9.0 is not released yet and both the snapshots and the default source trees have debugging enabled by default (which results in dramatic slowdowns so don't benchmark them without removing the debugging options).

If you're interested in how FreeBSD gets developed, you're encouraged to read the mailing lists and developer blogs.

Overall system / architectural changes

Kernel & low level improvements

Networking improvements

Storage subsystems' improvements

UFS SoftUpdates+Journal (SU+J)

Status: Pending commit to -CURRENT
Will appear in 9.0: sure
Author: Jeff Roberson
Web: discussion

A new feature added to existing UFS SoftUpdates code makes use of a small journal, technically an intent log, to keep track of metadata garbage collection which has upto now been left as a job for (background) fsck after an unclean shutdown. The intent behind this is to eliminate the requirement for fsck or background fsck on file systems with SoftUpdates enabled after unclean shutdown.

In effect, this feature combines the best of both worlds - the very fast operation of SoftUpdates with the removal of the need for fsck characteristic for journalling file systems. This is not a radical change - the well known SoftUpdates mechanism is still in its original form - but it completes the garbage collection step in a different way.

New driver for AHCI SATA drives

Status: Committed to -CURRENT, experimental
Will appear in 9.0: sure
Author: Alexandar Motin & others
Web: commit message

The new driver supports native AHCI via the CAM (common access method for storage) subsystem. AHCI drives are manipulated by camcontrol and support for new features like NCQ and port multipliers has been integrated. Among other features, performance has been significantly increased, port multipliers and hot-plugging are greatly improved.

ATA CAM implementation

Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Alexandar Motin
Web: commit message

The ATA disk drivers have all been moved to the CAM system, improving some features of them along the way. This makes CAM a very real central point and foundation of disk interfaces and management of (S)ATA, SCSI, USB and Firewire drives. Some SCSI controllers still have drivers outside CAM.

Improvements include: transfer size increase, better support for port multipliers.

Security

NFSv4 ACLs for UFS

Status: Committed to -CURRENT, MFC-ed
Will appear in 9.0: sure
Author: Edward Tomasz Napierala
Web: commit message

The well known and loved UFS file system has for some time implemented POSIX.1e ACLs (access control lists) in addition to the classic Unix file permissions model. This file permission model greatly enhances the way files can be managed and allows new security models to be implemented. It is also a standard part of the FreeBSD kernel, ready to be used at any time.

However, the POSIX.1e standard apparently never became trully widespread in practice. Through market share domination (but not completly without technical merit) the NTFS (Microsoft Windows file system) ACL security model has become widely popular and implemented, even so that it directly inspired the ACL model in the NFS (Network File System) version 4. The POSIX model is simpler and more Unix-like but the NTFS/NFSv4 model is more expressive.

The two ACL models are incompatible - security parameters set in NFSv4 model cannot always be directly translated to the POSIX model. Due to this and considering that NFSv4 ACLs are already directly implemented in ZFS, the introduction of NFSv4 ACLs in UFS is simply a feature-completness step which makes both file systems similarily usable from NFSv4 clients.

The POSIX model still remains in the implementation, but is mutualy exclusive (at the mount-point level) with the NFSv4 model.

Other changes

The following is a list of smaller and / or more obscure changes that nevertheless deserve a special mention since they will be of interest to certain users:

As always, all features described here are, or will be, a part of the FreeBSD "base" system, available in every FreeBSD installation without patching or out-of-the-ordinary configuration.

For more information about development of FreeBSD (among other topics), see my blog with daily and miscellaneous information.