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:
2011 / Q1
2010 / Q4
2010 / Q3
2010 / Q2
2010 / Q1
2009 / Q4
2009 / Q2+Q3
2009 / Q1
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
Userland DTrace
Status: committed to -CURRENT.
Will appear in 9.0: sure
Author: Rui Paulo
Web: announcement,
commit message
The kernel parts of the DTrace
system diagnostic framework were imported some time ago, but they are now
completed with the support for userland tracing, making it usable in general
userland software development and system administration. Userland DTrace is
already used in some large well known software packages such as
PostgreSQL
and X.Org.
CLANG / LLVM compiler
Status: Committed to -CURRENT.
Will appear in 9.0: yes
Authors: Roman Divacky, Pawel Worach, Ed Schouten and many others
Web: LLVM, CLANG,
FreeBSD wiki,
mailing list announcement
As the GCC compiler suite was relicensed under GPLv3 after the 4.2 release, and
the GPLv3 is a big dissapointment for some users of BSD systems (mostly commercial users
who have no-gplv3-beyond-company-doors policy),
having an alternative, non-GPL3 compiler for the base system has become highly
desireable. Currently, the overall consensus is that GCC 4.3 will not be imported
into the base system (the same goes for other GPLv3 code).
The LLVM and CLANG projects together offer a full BSD-licenesed C/C++ compiler
infrastructure that is, performance and feature-wise close to, or better than GCC.
The LLVM is the backend and the CLANG is the front-end part of the infrastructure.
Recent development has shown that not only is it possible to start using LLVM+CLANG
right away, it is also very stable. The probability of replacing GCC for the base
system in the near future is high. LLVM/CLANG will also add benefits to the overall system
such as better error reporting, Apple's Grand Central Dispatch system for
developing multithreaded applications and possibly JIT compiling some internal
structures like firewall rules.
Note that this mostly affects the base system. There is too much third party
software (e.g. ports) that depends on GCC to completely replace it.
Update: To make this happen, PathScale has developed and donated
the C++ runtime library under the BSD license.
PathScale has some other tools and libraries which may in the future help the transition
to a BSD-licensed toolkit: the assembler (pathas) and the debugger (pathDB).
Kernel & low level improvements
Large-scale SMP support
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Atillio Rao and others
Web: commit message
This work brings in support for large SMP systems, with more than 32 CPUs.
Previously, the kernel structures were unable to account for such a large
number of CPUs so the newest method implements extensible CPU accounting.
This is not an improvement in scalability in itself but is a prerequisite
for large-scale SMP work.
USB 3.0 support
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Hans Petter Selasky
Web: commit message
The new wave of USB changes improves on the hugely successful USB development
released in FreeBSD 8 and brings in support for USB 3.0.
Network kernel core dumps (netdump)
Status: In development
Will appear in 9.0: probably
Author: Attilio Rao and others
Web: announcement
Netdump is a framework that aims for handling kernel coredumps over
the TCP/IP suite in order to dump to a separate machine than the
running one. That may be used on an interesting number of cases
involving disk-less workstations, disk driver debugging or embedded
devices.
Initial NUMA support
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: John Baldwin
Web: Commit message,
discussion
As NUMA-like
architectures have become almost ubiqutous, even in i386 / amd64 architectures,
there are potentially big performance gains to be had in enabling its supports
within operating systems. New development aims to adapt the physical page allocator
to be NUMA-aware.
Modern event timer infrastructure
Status: Committed to -CURRENT
Will appear in 9.0: sure
Authors: Alexander Motin
Web: Commit message 1
Commit message 2
To better support the many sources of timer ticks present in todays system
and to build the foundation for tickless kernel, a new unifying timer infrastructure
was created. It currently supports
LAPIC, HPETs, i8254, RTC.
Tickless kernel
Status: Committed to -CURRENT
Will appear in 9.0: sure
Authors:Tsuyoshi Ozawa, Alexander Motin
Web: idea,
new timer infrastructure
To improve performance in virtual machines and power usage in laptops,
the "dynamic tick mode" (also called, a bit inappropriately, "tickless mode")
can replace the classic, strictly periodic hardware timer interrupt ticking
with one-shot variable-time ticks. This will save some CPU time which would
otherwise be spent handling timer interrupts which have no work assigned to
them. The tickless mode is enabled by default and can be turned off by
setting the kern.eventtimer.periodic to 1.
Networking improvements
High performance ssh
Status: Committed to -CURENT, MFC-ed
Will appear in 9.0: sure
Author: Brooks Davis
Web: commit message
SSH is commonly used for copying files but also for connection tunneling and
similar operations which stream a large amount of data over the encrypted
channels. The default configuration is somewhat conservative and does not
allow the full bandwidth potential of "fat and long" network connections to
be achived. The HPN-SSH
project has modified the ssh's flow control buffers to achieve much better
tranfer rate, and also includes a multithreaded cipher implementation which
makes such bandwidth sustainable on the CPU side. The results of the HPN-SSH
project (version 13) are now imported into FreeBSD.
More SMP-scalable TCP/IP
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Robert Watson
Web: commit message
announcement
Improvements to the networking stack introduce better scalability strategies based on the
work by Alan Cox and others.
With these changes, it is expected that the connections will have more clear CPU affinity,
less cache line contention and better use of modern hardware flow detection and handling.
New NFS client and server
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Rick Macklem
Web: commit message
The new NFS client and server introduce the support for NFSv4 as their
biggest features, with ACL support, byte range locking and delegation support.
It should also be easier to maintain and later upgrate do NFSv4.1
Five new TCP congestion algorithms
Status: Partially committed to -CURRENT
Will appear in 9.0: sure
Author: Lawrence Stewart
Web: Commit message
This commit marks the first formal contribution of the "Five New TCP Congestion
ontrol Algorithms for FreeBSD" FreeBSD Foundation funded project. More details
about the project are available at:
http://caia.swin.edu.au/freebsd/5cc/.
SIFTR - Statistical Information for TCP Research
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Lawrence Stewart
Web: commit message
SIFTR logs a range of statistics on active TCP connections to a log
file, providing the ability to make highly granular measurements of TCP
connection state. The tool is aimed at system administrators, developers and
researchers.
Storage subsystems' improvements
CAM enclosure update
Status: committed
Will appear in 9.0: sure
Authors: Justin T. Gibbs
Web: commit message
Revamp the CAM enclosure services driver, renaming it to "enc" from "ses" in
the process. This updated driver uses an in-kernel daemon to track state
changes and publishes physical path location information for disk elements
into the CAM device database.
-->
A move to support 4K drives
Status: committed
Will appear in 9.0: sure
Authors: Kirk McKusick, Alexandar Motin, Andrey V. Elsukov and others
Web: UFS fragment size commit, SATA quirks commit,
gpart alignment calculation
FreeBSD's GEOM and file systems have intrinsically supported large (or even arbitrary)
sector sizes for a long time, but there is still the issue of detecting them and
communicating this information across the layers. Some new development introduced SATA quirks
to detect known 4K drives (with the ability for users to set their own quirks on non-detected
drives), the gpart(8) utility will calculate the correct alignment or warn on misalignment,
and the default fragment / block size for UFS was changed to 4K / 32K.
Generic GEOM IO schedulers
Status: Committed to -CURRENT
Will appear in 9.0: sure
Authors: Luigi Rizzo, Fabio Checconi
Web: commit message
The new framework, integrated with GEOM, allows for multiple disk IO
schedulers to be used, if necessary, on different IO providers (e.g. drives).
The usage of some IO schedulers can increase responsiveness in certain kinds
of IO workloads, for example a mix of sequential and random IO.
HAST - High Availability Storage
Status: Committed to -CURRENT, planned MFC
Will appear in 9:0: sure
Author: Pawel Jakub Dawidek
Web: FreeBSD wiki page
HAST is a userland-based (ggate) implementation of a distributed storage device
concept, similar to Linux's DRBD. It allows over-the-network mirroring of any GEOM
storage devices in a semi-synchronous way (writes suceed when the data is sent
over the wire).
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, MFC-ed
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
Capsicum
Status: Basic functions committed to -CURRENT
Will appear in 9.0: sure
Author: Robert Watson and others
Web: commit message
Capsicum is a framework for security isolation of sensitive processes,
which may prove useful in security strengthening the operating system.
AES-XTS encryption mode in kernel
Status: Committed to -CURRENT
Will appear in 9.0: sure
Author: Pawel Jakub Dawidek
Web:
AES-XTS in kernel
AES-XTS in GELI
AES-XTS via AESNI
The XTS block cypher mode
is specially suited for encrypting disk drives and other block devices. It
avoids some security problems arising with using plain CBC chaining with
addressible-sector encryption.
AES with XTS mode is used in GELI and is also supported when implemented via
the AES-NI.
NFSv4 ACLs for UFS
Status: Committed to -CURRENT, MFCed
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:
A new utility called fuser, used to get a list of processes which have one or more files open. It can be used
to get a list of processes having an open file on a mount point (stas)
Default UFS block & fragment sizes increased to 32 KiB / 4 KiB (mckusick)
BSD licensed grep (obrien)
Support for ATA/AHCI per-device write cache disable (mav)
Syscall performance regression fixed (jhb)
Resource accounting (a part of resource container work) (trasz)
Improvements to CPU detection (jkim)
Many bug fixes to hastd (pjd)
ZFS updated to version 28 (pjd)
Beginnings of process-kernel shared page infrastructure (kib)
TRIM (BIO_DELETE) support for UFS (kib)
MCA (Machine check architecture) logging enabled by default (jhb)
usbdump kernel facility and tool (weongyo)
New log rotation file system naming scheme with newsyslog, using timestamps (simon) [MFC-ed]
GELI secure suspend/resume functionality (pjd)
TPM driver (takawata et al)
Increased read-ahead and write queue UFS buffers for better NCQ utilization (ivoras)
AESNI (Nehalem CPU instruction) crypto(4) driver (kib)
DAHDI (Digium/Asterix Hardware Device Interface drivers
Resource containers (trasz)
ZFS updated to version 15 and synced with modern performance improvements (mm)
TLB shootdowns optimizations (alc)
Important fixes to tmpfs memory use and stability (kib)
Significant BSNMPD enhancements (syrinx)
Default SYSV semaphore and SHM sizes increased (ivoras)
Jails can be nested / hierarchical (jamie)
Jails / virtual network stack / os-level virtualization improvements (bz)
Import of xz and liblzma into the base system (mm)
EFI boot loader (rpaulo)
The FreeBSD logo integrated
into syscon screensaver (jkim)
ZFS performance and
stability improvements
(kmacy)
Inter-process shared userland semaphores
(davidxu)
ZFS updated to version 14 (delphij) [MFC-ed]
Implemented TRIM / ERASE
(S)ATA commands for SSDs and similar drives, notifying them of unused
disk space so it can be reclaimed (mav)
Updated gmirror (software RAID-1) load balancing (mav) [MFC-ed]
Solaris-like pwait(1) utility (jilles) [MFC-ed],
refactored rc.d to use pwait(1).
IPFW becomes VNET-aware (virtualized network stack, i.e. a firewall
instance per jail/VNET) and gets more SMP performance. (luigi)
Imported V4L (video 4 linux) support in the Linuxulator
(aka Linux compatibility mode) (netchild)
Better support for Machine Check Exceptions (jb)
Reworked utmp system (ed)
Open-source 3D hardware acceleration for Radeon HD cards (nork, rnoland)
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.