c19895c624
for reasons beyond comprehension. Specifically document the following features now present in mainstream releases: - Multithreaded SMP architecture and support for preemption. - M:N threading out of the box. - File system snapshots and background fsck. - Netgraph pluggable network stack framework. - TrustedBSD MAC Framework. - GEOM. This page could use more work in other ways also...
151 lines
6.4 KiB
Text
151 lines
6.4 KiB
Text
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" [
|
|
<!ENTITY date "$FreeBSD: www/en/features.sgml,v 1.22 2004/11/17 21:54:32 rushani Exp $">
|
|
<!ENTITY title "About FreeBSD's Technological Advances">
|
|
<!ENTITY % includes SYSTEM "includes.sgml"> %includes;
|
|
]>
|
|
|
|
<html>
|
|
&header;
|
|
|
|
<h1>FreeBSD offers many advanced features.</h1>
|
|
|
|
<blockquote>
|
|
<p>No matter what the application, you want your system's resources
|
|
performing at their full potential. FreeBSD's advanced features
|
|
enable you to do just that.</p>
|
|
</blockquote>
|
|
|
|
<hr align="left" noshade="noshade" width="100%"><font
|
|
color="#FF0000"><font size="+1">A complete operating system based on
|
|
4.4BSD.</font></font>
|
|
|
|
<blockquote>
|
|
<p>FreeBSD's distinguished roots derive from the latest <b>BSD</b>
|
|
software releases from the Computer Systems Research Group at the
|
|
University of California, Berkeley. The book <i>The Design and
|
|
Implementation of 4.4BSD Operating System</i>, written by the 4.4BSD
|
|
system architects, thus describes much of FreeBSD's core functionality
|
|
in detail.</p>
|
|
|
|
<p>Drawing on the skills and experience of a diverse and world-wide
|
|
group of volunteer developers, the FreeBSD Project has worked to
|
|
extend the feature set of the 4.4BSD operating system in many ways,
|
|
striving constantly to make each new release of the OS more stable,
|
|
faster and containing new functionality driven by user requests.</p>
|
|
</blockquote>
|
|
|
|
<hr align="left" noshade="noshade" width="100%"><font
|
|
color="#FF0000"><font size="+1">FreeBSD provides higher performance,
|
|
greater compatibility with other operating systems and less system
|
|
administration.</font></font>
|
|
|
|
<blockquote>
|
|
<p>FreeBSD's developers attacked some of the more difficult problems in
|
|
operating systems design to give you these advanced features:</p>
|
|
|
|
<ul>
|
|
<li><b>A merged virtual memory and filesystem buffer cache</b>
|
|
continuously tunes the amount of memory used for programs and the
|
|
disk cache. As a result, programs receive both excellent memory
|
|
management and high performance disk access, and the system
|
|
administrator is freed from the task of tuning cache sizes.</li>
|
|
|
|
<li><b>Compatibility modules</b> enable programs for other operating
|
|
systems to run on FreeBSD, including programs for Linux, SCO UNIX,
|
|
and System V Release 4.</li>
|
|
|
|
<li><b>Soft Updates</b> allows improved filesystem
|
|
performance without sacrificing safety and reliability.
|
|
It analyzes meta-data filesystem operations to avoid having
|
|
to perform all of those operations synchronously.
|
|
Instead, it maintains internal state about pending meta-data
|
|
operations and uses this information to cache meta-data,
|
|
rewrite meta-data operations to combine subsequent
|
|
operations on the same files, and reorder meta-data
|
|
operations so that they may be processed more efficiently.</li>
|
|
|
|
<li><b>Support for IPsec and IPv6</b> allows improved security in
|
|
networks, and support for the next-generation Internet Protocol,
|
|
IPv6. The FreeBSD IPSEC implementation includes support for a
|
|
broad range of accelerated crypto hardware.</li>
|
|
|
|
<li><b>Multi-threaded SMP architecture</b> capable of executing the
|
|
kernel in parallel on multiple processors, and with <b>kernel
|
|
preemption</b>, allowing high priority kernel tasks to preempt
|
|
other kernel activity, reducing latency. This includes a
|
|
<b>multi-threaded network stack</b> and a <b>multi-threaded
|
|
virtual memory subsystem</b>.</li>
|
|
|
|
<li><b>M:N threading application threading</b> permitting threads to
|
|
execute on multiple CPUs in a scaleable manner, mapping many user
|
|
threads onto a small number of <b>Kernel Schedulable Entities</b>.
|
|
By adopting the <b>Scheduler Activation</b> model, the threading
|
|
model can be adapted to the specific requirements of a broad range
|
|
of applications.</li>
|
|
|
|
<li><b>File system snapshots</b>, permitting administrators to take
|
|
atomic file system snapshots for backup purposes using the free
|
|
space in the file system, as well as facilitating <b>background
|
|
fsck</b>, which allows the system to reach multiuser mode without
|
|
waiting on file system cleanup operations following power outages.
|
|
</li>
|
|
|
|
<li><b>Netgraph pluggable network stack</b> allows developers to
|
|
dynamically and easily extend the network stack through clean
|
|
layered network abstractions. Netgraph nodes can implement a broad
|
|
range of new network services, including encapsulation, tunneling,
|
|
encryption, and performance adaptation.</li>
|
|
|
|
<li><b>TrustedBSD MAC Framework extensible kernel security</b>,
|
|
which allows developers to customize the operating system security
|
|
model for specific environments, from creating hardening policies
|
|
to deploying mandatory labeled confidentiality of integrity
|
|
policies.</li>
|
|
|
|
<li><b>GEOM pluggable storage layer</b>, which permits new storage
|
|
services to be quickly developed and cleanly integrated into the
|
|
FreeBSD storage subsystem. GEOM provides a consistent and
|
|
coherrent model for discovering and layering storage services,
|
|
making it possible to layer services such as RAID and volume
|
|
management easily.</li>
|
|
|
|
<li><b>Kernel Queues</b> allow programs to respond more efficiently
|
|
to a variety of asynchronous events including file and socket IO,
|
|
improving application and system performance.</li>
|
|
|
|
<li><b>Accept Filters</b> allow connection-intensive applications,
|
|
such as web servers, to cleanly push part of their functionality into
|
|
the operating system kernel, improving performance.</li>
|
|
</ul>
|
|
|
|
</blockquote>
|
|
|
|
<hr align="left" noshade="noshade" width="100%"><font
|
|
color="#FF0000"><font size="+1">FreeBSD provides many security features
|
|
to protect networks and servers.</font></font>
|
|
|
|
<blockquote>
|
|
<p>The FreeBSD developers are as concerned about security as they are
|
|
about performance and stability. FreeBSD includes kernel support for
|
|
stateful IP firewalling, as well as other services, such as IP proxy
|
|
gateways.</p>
|
|
|
|
<p>FreeBSD also includes support for encryption software, secure
|
|
shells, Kerberos authentication, "virtual servers" created using
|
|
jails, chroot-ing services to restrict application access to the
|
|
file system, Secure RPC facilities, and access lists for services
|
|
that support TCP wrappers.</p>
|
|
</blockquote>
|
|
|
|
&footer;
|
|
</body>
|
|
</html>
|
|
|
|
<!--
|
|
Local Variables:
|
|
mode: sgml
|
|
sgml-indent-data: t
|
|
sgml-omittag: nil
|
|
sgml-always-quote-attributes: t
|
|
End:
|
|
-->
|