release/doc/en_US.ISO8859-1/relnotes/article.xml

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   4 <!ENTITY % release PUBLIC "-//FreeBSD//ENTITIES Release Specification//EN" "release.ent">
   5  %release;
   6 <!ENTITY % sponsor PUBLIC "-//FreeBSD//ENTITIES Sponsor Specification//EN" "sponsor.ent">
   7  %sponsor;
   8 <!ENTITY % vendor PUBLIC "-//FreeBSD//ENTITIES Vendor Specification//EN" "vendor.ent">
   9  %vendor;
  10 <!ENTITY security SYSTEM "../../share/xml/security.xml">
  11 <!ENTITY errata SYSTEM "../../share/xml/errata.xml">
  12 ]>
  13 <article xmlns="http://docbook.org/ns/docbook"
  14   xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0">
  15
  16   <info>
  17     <title>&os; &release.current; Release Notes</title>
  18
  19     <author>
  20       <orgname>The &os; Project</orgname>
  21     </author>
  22
  23     <pubdate>$FreeBSD$</pubdate>
  24
  25     <!-- Last rev: 282482 -->
  26
  27     <copyright>
  28       <year>2015</year>
  29       <holder role="mailto:doc@FreeBSD.org">The &os; Documentation
  30         Project</holder>
  31     </copyright>
  32
  33     <legalnotice xml:id="trademarks" role="trademarks">
  34       &tm-attrib.freebsd;
  35       &tm-attrib.ibm;
  36       &tm-attrib.ieee;
  37       &tm-attrib.intel;
  38       &tm-attrib.sparc;
  39       &tm-attrib.general;
  40     </legalnotice>
  41
  42     <abstract>
  43       <para>The release notes for &os; &release.current; contain
  44         a summary of the changes made to the &os; base system on the
  45         &release.branch; development line.  This document lists
  46         applicable security advisories that were issued since the last
  47         release, as well as significant changes to the &os; kernel and
  48         userland.  Some brief remarks on upgrading are also
  49         presented.</para>
  50     </abstract>
  51   </info>
  52
  53   <sect1 xml:id="intro">
  54     <title>Introduction</title>
  55
  56     <para>This document contains the release notes for &os;
  57       &release.current;.  It describes recently added, changed, or
  58       deleted features of &os;.  It also provides some notes on
  59       upgrading from previous versions of &os;.</para>
  60
  61     <para releasetype="current">The &release.type; distribution to
  62       which these release notes apply represents the latest point
  63       along the &release.branch; development branch since
  64       &release.branch; was created.  Information regarding pre-built,
  65       binary &release.type; distributions along this branch can be
  66       found at <uri
  67         xlink:href="&release.url;">&release.url;</uri>.</para>
  68
  69     <para releasetype="snapshot">The &release.type; distribution to
  70       which these release notes apply represents a point along the
  71       &release.branch; development branch between &release.prev; and
  72       the future &release.next;.  Information regarding pre-built,
  73       binary &release.type; distributions along this branch can be
  74       found at <uri
  75         xlink:href="&release.url;">&release.url;</uri>.</para>
  76
  77     <para releasetype="release">This distribution of &os;
  78       &release.current; is a &release.type; distribution.  It can be
  79       found at <uri xlink:href="&release.url;">&release.url;</uri> or
  80       any of its mirrors.  More information on obtaining this (or
  81       other) &release.type; distributions of &os; can be found in the
  82       <link
  83         xlink:href="&url.books.handbook;/mirrors.html"><quote>Obtaining
  84           &os;</quote> appendix</link> to the <link
  85         xlink:href="&url.books.handbook;/">&os;
  86         Handbook</link>.</para>
  87
  88     <para>All users are encouraged to consult the release errata
  89       before installing &os;.  The errata document is updated with
  90       <quote>late-breaking</quote> information discovered late in the
  91       release cycle or after the release.  Typically, it contains
  92       information on known bugs, security advisories, and corrections
  93       to documentation.  An up-to-date copy of the errata for &os;
  94       &release.current; can be found on the &os; Web site.</para>
  95
  96     <para>This document describes the most user-visible new or changed
  97       features in &os; since &release.prev;.  In general, changes
  98       described here are unique to the &release.branch; branch unless
  99       specifically marked as &merged; features.</para>
 100
 101     <para>Typical release note items document recent security
 102       advisories issued after &release.prev;, new drivers or hardware
 103       support, new commands or options, major bug fixes, or
 104       contributed software upgrades.  They may also list changes to
 105       major ports/packages or release engineering practices.  Clearly
 106       the release notes cannot list every single change made to &os;
 107       between releases; this document focuses primarily on security
 108       advisories, user-visible changes, and major architectural
 109       improvements.</para>
 110   </sect1>
 111
 112   <sect1 xml:id="upgrade">
 113     <title>Upgrading from Previous Releases of &os;</title>
 114
 115     <para arch="amd64,i386">Binary upgrades between RELEASE versions
 116       (and snapshots of the various security branches) are supported
 117       using the &man.freebsd-update.8; utility.  The binary upgrade
 118       procedure will update unmodified userland utilities, as well as
 119       unmodified GENERIC kernels distributed as a part of an official
 120       &os; release.  The &man.freebsd-update.8; utility requires that
 121       the host being upgraded have Internet connectivity.</para>
 122
 123     <para>Source-based upgrades (those based on recompiling the &os;
 124       base system from source code) from previous versions are
 125       supported, according to the instructions in
 126       <filename>/usr/src/UPDATING</filename>.</para>
 127
 128     <important>
 129       <para>Upgrading &os; should only be attempted after backing up
 130         <emphasis>all</emphasis> data and configuration files.</para>
 131     </important>
 132   </sect1>
 133
 134   <sect1 xml:id="security-errata">
 135     <title>Security and Errata</title>
 136
 137     <para>This section lists the various Security Advisories and
 138       Errata Notices since &release.prev;.</para>
 139
 140     <sect2 xml:id="security">
 141       <title>Security Advisories</title>
 142
 143       &security;
 144     </sect2>
 145
 146     <sect2 xml:id="errata">
 147       <title>Errata Notices</title>
 148
 149       &errata;
 150     </sect2>
 151   </sect1>
 152
 153   <sect1 xml:id="userland">
 154     <title>Userland</title>
 155
 156     <para>This section covers changes and additions to userland
 157       applications, contributed software, and system utilities.</para>
 158
 159     <sect2 xml:id="userland-config">
 160       <title>Userland Configuration Changes</title>
 161
 162       <para revision="266463">The default &man.newsyslog.conf.5; now
 163         includes files in the
 164         <filename>/etc/newsyslog.conf.d/</filename> and
 165         <filename>/usr/local/etc/newsyslog.conf.d/</filename>
 166         directories by default for &man.newsyslog.8;.</para>
 167
 168       <para revision="270675">The &man.mailwrapper.8; utility has been
 169         updated to use &man.mailer.conf.5; from the
 170         <literal>LOCALBASE</literal> environment variable, which
 171         defaults to <filename class="directory">/usr/local</filename>
 172         if unset.</para>
 173
 174       <para revision="272350">The <literal>MK_ARM_EABI</literal>
 175         &man.src.conf.5; option has been removed.</para>
 176     </sect2>
 177
 178     <sect2 xml:id="userland-programs">
 179       <title>Userland Application Changes</title>
 180
 181       <para revision="258838" contrib="sponsor" sponsor="&ff;,
 182         &google;" sponsorurl="">The &man.casperd.8; daemon has been
 183         added, which provides access to functionality that is not
 184         available in the <quote>capability mode</quote>
 185         sandbox.</para>
 186
 187       <para revision="260594">When unable to load a kernel module with
 188         &man.kldload.8;, a message informing to view output of
 189         &man.dmesg.8; is now printed, opposed to the previous output
 190         <quote>Exec format error.</quote>.</para>
 191
 192       <para revision="260910">Allow &man.pciconf.8; to identify PCI
 193         devices that are attached to a driver to be identified by
 194         their device name instead of just the selector.  Additionally,
 195         an optional device argument to the <literal>-l</literal> flag
 196         to restrict the output to only listing details about a single
 197         device.</para>
 198
 199       <para revision="260913">A new flag, <quote>onifconsole</quote>
 200         has been added to <filename>/etc/ttys</filename>.  This allows
 201         the system to provide a login prompt via serial console if the
 202         device is an active kernel console, otherwise it is equivalent
 203         to <literal>off</literal>.</para>
 204
 205       <para revision="260926">Support for displaying VPD for PCI
 206         devices via &man.pciconf.8; has been added.</para>
 207
 208       <para revision="261498">&man.ping.8; protects against malicious
 209         network packets using the Capsicum framework to drop
 210         privileges.</para>
 211
 212       <para revision="265229">The &man.ps.1; utility has been
 213         updated to include the <literal>-J</literal> flag, used to
 214         filter output by matching &man.jail.8; IDs and names.
 215         Additionally, argument <literal>0</literal> can be used to
 216         <literal>-J</literal> to only list processes running on the
 217         host system.</para>
 218
 219       <para revision="265249">The &man.top.1; utility has been updated
 220         to filter by &man.jail.8; ID or name, in followup to the
 221         &man.ps.1; change in <literal>r265229</literal>.</para>
 222
 223       <para revision="265995">The Blowfish &man.crypt.3; default
 224         format has been changed to
 225         <literal>&dollar;2b&dollar;</literal>.</para>
 226
 227       <para revision="266209">The &man.pmcstat.8; utility has been
 228         updated to include a new flag, <literal>-l</literal>, which
 229         ends event collection after the specified number of
 230         seconds.</para>
 231
 232       <para revision="270745">The &man.ps.1; utility has been updated
 233         to include a new keyword, <quote>tracer</quote>, which
 234         displays the <acronym>PID</acronym> of the tracing
 235         process.</para>
 236
 237       <para revision="271482">Support for adding empty partitions has
 238         been added to the &man.mkimg.1; utility.</para>
 239
 240       <para revision="272166">The &man.primes.6; utility has been
 241         updated to correctly enumerate prime numbers between
 242         <literal>4295098369</literal> and
 243         <literal>3825123056546413050</literal>, which prior to this
 244         change, it would be possible for returned values to be
 245         incorrectly identified as prime numbers.</para>
 246
 247       <para revision="272198">The &man.mkimg.1; utility has been
 248         updated to include three options used to print information
 249         about &man.mkimg.1; itself:</para>
 250
 251       <informaltable frame="none" pgwide="0">
 252         <tgroup cols="2">
 253           <colspec colwidth="1*"/>
 254           <colspec colwidth="1*"/>
 255           <thead>
 256             <row>
 257               <entry>Option</entry>
 258               <entry>Output</entry>
 259             </row>
 260           </thead>
 261
 262           <tbody>
 263             <row>
 264               <entry><literal>--version</literal></entry>
 265               <entry>The current version of the &man.mkimg.1;
 266                 utility</entry>
 267             </row>
 268
 269             <row>
 270               <entry><literal>--formats</literal></entry>
 271               <entry>The disk image file formats supported by
 272                 &man.mkimg.1;</entry>
 273             </row>
 274
 275             <row>
 276               <entry><literal>--schemes</literal></entry>
 277               <entry>The partition schemes supported by
 278                 &man.mkimg.1;</entry>
 279             </row>
 280           </tbody>
 281         </tgroup>
 282       </informaltable>
 283
 284       <para revision="272488">Userland &man.ctf.5; support in
 285         &man.dtrace.1; has been added.  With this change,
 286         &man.dtrace.1; is able to resolve type info for function and
 287         <acronym>USDT</acronym> probe arguments, and function return
 288         values.</para>
 289
 290       <para revision="274960">The &man.elfdump.1; utility has been
 291         updated to support capability mode provided by
 292         &man.capsicum.4;.</para>
 293
 294       <para revision="275680" contrib="sponsor" sponsor="&ff;">The
 295         &man.fstyp.8; utility has been added, which is used to
 296         determine the filesystem on a specified device.</para>
 297
 298       <para revision="276881">The <literal>libedit</literal> library
 299         has been updated to support <acronym>UTF</acronym>-8, which
 300         additionally provides unicode support to &man.sh.1;.</para>
 301
 302       <para revision="277166" arch="powerpc">The &man.ptrace.2; system
 303         call has been updated include support for Altivec registers on
 304         &os;/&arch.powerpc;.</para>
 305
 306       <para revision="278320">A new device control utility,
 307         &man.devctl.8; has been added, which allows making
 308         administrative changes to individual devices, such as
 309         attaching and detaching drivers, and enabling and disabling
 310         devices.  The &man.devctl.8; utility uses the new
 311         &man.devctl.3; library.</para>
 312
 313       <para revision="279315" contrib="sponsor" sponsor="&ff;">The
 314         &man.uefisign.8; utility has been added.</para>
 315
 316       <para revision="279571" contrib="sponsor"
 317         sponsor="&scaleengine;">The &man.freebsd-update.8; utility has
 318         been updated to prevent fetching updated binary patches when
 319         a previous upgrade has not been thoroughly completed.</para>
 320
 321       <para revision="279122" contrib="sponsor"
 322         sponsor="&juniper;">The &man.netstat.1; utility has been
 323         updated to link against the &man.libxo.3; shared
 324         library.</para>
 325
 326       <para revision="280870">A regression in the &man.libarchive.3;
 327         library that would prevent a directory from being included in
 328         the archive when <literal>--one-file-system</literal> is used
 329         has been fixed.</para>
 330
 331       <para revision="281311" contrib="sponsor" sponsor="&ff;">The
 332         &man.ar.1; utility has been updated to set
 333         <literal>ARCHIVE_EXTRACT_SECURE_SYMLINKS</literal> and
 334         <literal>ARCHIVE_EXTRACT_SECURE_NODOTDOT</literal> to disallow
 335         directory traversal when extracting an archive, similar to
 336         &man.tar.1;.</para>
 337
 338       <para revision="282208" contrib="sponsor"
 339         sponsor="&multiplay;">The &man.chflags.1;, &man.chgrp.1;,
 340         &man.chmod.1;, and &man.chown.8; utilities now affect symbolic
 341         links when the <literal>-R</literal> flag is specified, as
 342         documented in &man.symlink.7;.</para>
 343
 344       <para revision="281617">A race condition in &man.wc.1; that
 345         would cause final results to be sent to &man.stderr.4; when
 346         receiving the <literal>SIGINFO</literal> signal has been
 347         fixed.</para>
 348
 349       <para revision="284297" contrib="sponsor"
 350         sponsor="&clusterhq;">The &man.lockstat.1; utility has been
 351         updated with several improvements:</para>
 352
 353       <itemizedlist>
 354         <listitem>
 355           <para>Spin locks are now reported as the amount of time
 356             spinning, instead of loop iterations.</para>
 357         </listitem>
 358
 359         <listitem>
 360           <para>Reader locks are now recognized as adaptive and can
 361             spin on &os;.</para>
 362         </listitem>
 363
 364         <listitem>
 365           <para>Lock aquisition events for successful reader try-lock
 366             events are now reported.</para>
 367         </listitem>
 368
 369         <listitem>
 370           <para>Spin-and-block events that occur before lock
 371             acquisition are now reported.</para>
 372         </listitem>
 373       </itemizedlist>
 374     </sect2>
 375
 376     <sect2 xml:id="userland-contrib">
 377       <title>Contributed Software</title>
 378
 379       <para revision="258884" contrib="sponsor"
 380         sponsor="&darpa_afrl;">&man.lldb.1; has been updated to
 381         upstream snapshot version r196259.</para>
 382
 383       <para revision="259626">Timezone data files have been updated to
 384         version 2013i.</para>
 385
 386       <para revision="260445">&man.byacc.1; has been updated to
 387         version 20140101.</para>
 388
 389       <para revision="261071">&man.jemalloc.3; has been updated to
 390         version 3.5.0.</para>
 391
 392       <para revision="261283"><application>libc++</application> has
 393         been updated to version 3.4.</para>
 394
 395       <para revision="261320"><application>OpenSSH</application> has
 396         been updated to 6.5p1.</para>
 397
 398       <para revision="261344"><application>mdocml</application> has
 399         been updated to version 1.12.3.</para>
 400
 401       <para revision="261991"><application>LLVM</application> and
 402         <application>Clang</application> have been updated to
 403         version 3.4.</para>
 404
 405       <para revision="266527"
 406         role="merged"><application>Sendmail</application> has been
 407         updated from 8.14.7 to 8.14.9.</para>
 408
 409       <para revision="276577"><application>file</application> has been
 410         updated to version 5.22.</para>
 411
 412       <para revision="275718">The <application>binutils</application>
 413         suite of utilities has been updated to include upstream
 414         patches that add new relocations for &arch.powerpc;
 415         support.</para>
 416
 417       <para revision="276398" contrib="sponsor" sponsor="&ff;">The
 418         <application>ELF Tool Chain</application> has been updated to
 419         upstream revision r3136.</para>
 420
 421       <para revision="276551">The <application>texinfo</application>
 422         utility and <literal>info</literal> pages were removed from
 423         the base system.  The <filename
 424           role="package">print/texinfo</filename> port should be
 425         installed on systems where <literal>info</literal> pages are
 426         needed.</para>
 427
 428       <para revision="276796" contrib="sponsor" sponsor="&ff;">The ELF
 429         object manipulation tools
 430         <application>addr2line</application>,
 431         <application>elfcopy (strip)</application>,
 432         <application>nm</application>,
 433         <application>readelf</application>,
 434         <application>size</application>, and
 435         <application>strings</application> were switched to the
 436         versions from the ELF Tool Chain project.</para>
 437
 438       <para revision="276881">The <literal>libedit</literal> library
 439         has been updated to include <acronym>UTF-8</acronym> support,
 440         adding <acronym>UTF-8</acronym> support to the &man.sh.1;
 441         shell.</para>
 442
 443       <para revision="278433">The &man.xz.1; utility has been updated
 444         to support multi-threaded compression.</para>
 445
 446       <para revision="280297"><application>OpenSSL</application> has
 447         been updated to version 1.0.1m.</para>
 448
 449       <para revision="280932" contrib="sponsor" sponsor="&ff;">The
 450         <application>elftoolchain</application> utilities have been
 451         updated to version 3179.</para>
 452
 453       <para revision="281316">The &man.xz.1; utility has been updated
 454         to version 5.2.1.</para>
 455
 456       <para revision="281373">The &man.nvi.1; utility has been updated
 457         to version 2.1.3.</para>
 458
 459       <para revision="281396">The &man.acpi.4; subsystem has been
 460         updated to version 20150410.</para>
 461
 462       <para revision="281806">The &man.wpa.supplicant.8; and
 463         &man.hostapd.8; utilities have been updated to version
 464         2.4.</para>
 465
 466       <para revision="282089">The &man.unbound.8; utility has been
 467         updated to version 1.5.3.</para>
 468
 469       <para revision="282434" contrib="sponsor" sponsor="&ff;">The
 470         &man.resolvconf.8; utility has been updated to version
 471         3.7.0.</para>
 472
 473       <para revision="284254"><application>bmake</application> has
 474         been updated to version 20150606.</para>
 475     </sect2>
 476
 477     <sect2 xml:id="userland-installer">
 478       <title>Installation and Configuration Tools</title>
 479
 480       <para revision="271539">The &man.bsdinstall.8; partition editor
 481         and &man.sade.8; utility have been updated to include native
 482         <acronym>ZFS</acronym> support.</para>
 483
 484       <para revision="272274">The &os; installation utility,
 485         &man.bsdinstall.8;, has been updated to set the
 486         <literal>canmount</literal> &man.zfs.8; property to
 487         <literal>off</literal> for the <filename
 488           class="directory">/var</filename> dataset, preventing the
 489         contents of directories within <filename
 490           class="directory">/var</filename> from conflicting when
 491         using multiple boot environments, such as that provided by
 492         <filename role="package">sysutils/beadm</filename>.</para>
 493
 494       <para revision="274394">The &man.bsdconfig.8; utility has been
 495         updated to skip the initial &man.tzsetup.8;
 496         <acronym>UTC</acronym> versus wall-clock time prompt when run
 497         in a virtual machine, determined when the
 498         <literal>kern.vm_guest</literal> &man.sysctl.8; is set to
 499         <literal>1</literal>.</para>
 500
 501       <para revision="275874">The &man.bsdinstall.8; utility has been
 502         updated to use the new &man.dpv.3; library to display progress
 503         when extracting the &os; distributions.</para>
 504     </sect2>
 505
 506     <sect2 xml:id="userland-rc">
 507       <title><filename class="directory">/etc/rc.d</filename>
 508         Scripts</title>
 509
 510       <para revision="270676">The &man.rc.8; subsystem has been
 511         updated to allow configuring services in <filename
 512           class="directory">&dollar;{LOCALBASE}/etc/rc.conf.d/</filename>.
 513         If <literal>LOCALBASE</literal> is unset, it defaults to
 514         <filename class="directory">/usr/local</filename>.</para>
 515
 516       <para revision="275299">The <filename>mrouted</filename>
 517         &man.rc.8; script has been removed from the base system.  An
 518         equivalent script is available from the <filename
 519           role="package">net/mrouted</filename> port.</para>
 520
 521       <para revision="279463" contrib="sponsor"
 522         sponsor="&sandvine;">A new &man.rc.8; script,
 523         <filename>iovctl</filename>, has been added, which allows
 524         automatically starting the &man.iovctl.8; utility at
 525         boot.</para>
 526     </sect2>
 527
 528     <sect2 xml:id="userland-periodic">
 529       <title><filename class="directory">/etc/periodic</filename>
 530         Scripts</title>
 531
 532       <para revision="271321">The daily &man.periodic.8; script
 533         <filename>110.clean-tmps</filename> has been updated to avoid
 534         crossing filesystem mount boundaries when cleaning files in
 535         <filename class="directory">/tmp</filename>.</para>
 536     </sect2>
 537
 538     <sect2 xml:id="userland-libraries">
 539       <title>Runtime Libraries and API</title>
 540
 541       <para revision="268461">The &man.readline.3; library is now
 542         statically linked in software within the base system, and the
 543         shared library is no longer installed, allowing the Ports
 544         Collection to use a modern version of the library.</para>
 545
 546       <para revision="272273">The &man.strptime.3; library has been
 547         updated to add support for <acronym>POSIX</acronym>-2001
 548         features <literal>%U</literal> and
 549         <literal>%W</literal>.</para>
 550
 551       <para revision="272842,272848" contrib="sponsor"
 552         sponsor="&ff;">The &man.dl.iterate.phdr.3; library has been
 553         changed to always return the path name of the
 554         <acronym>ELF</acronym> object in the
 555         <literal>dlpi_name</literal> structure member.</para>
 556
 557       <para revision="273562" contrib="sponsor"
 558         sponsor="&juniper;">The &man.libxo.3; library has been
 559         imported to the base system.</para>
 560
 561       <para revision="273806" contrib="sponsor" sponsor="&chelsio;">A
 562         userland library for Chelsio Terminator 5 based iWARP cards
 563         has been added, allowing userland <acronym>RDMA</acronym>
 564         applications to work over compatible
 565         <acronym>NIC</acronym>s.</para>
 566
 567       <para revision="274987">The &man.gpio.3; library has been added,
 568         providing a wrapper around the &man.gpio.4; kernel
 569         interface.</para>
 570
 571       <para revision="277610">The <literal>futimens()</literal> and
 572         <literal>utimensat()</literal> system calls have been
 573         added.  See &man.utimensat.2; for more information.</para>
 574
 575       <para revision="278934">The &man.elf.3; compile-time dependency
 576         has been removed from <filename>dtri.o</filename>, which
 577         allows adding <application>DTrace</application> probes to
 578         userland applications and libraries without also linking
 579         against &man.elf.3;.</para>
 580
 581       <para revision="279186">The &man.setmode.3; function has been
 582         updated to consistently set <literal>errno</literal> on
 583         failure.</para>
 584
 585       <para revision="279663">The &man.qsort.3; functions have been
 586         updated to be able to handle 32-bit aligned data on 64-bit
 587         platforms, also providing a significant improvement in 32-bit
 588         workloads.</para>
 589
 590       <para revision="281130">Several standard include headers have
 591         been updated to use of <application>gcc</application>
 592         attributes, such as <literal>__result_use_check()</literal>,
 593         <literal>__alloc_size()</literal>, and
 594         <literal>__nonnull()</literal>.</para>
 595
 596       <para revision="281845">Support for file verification in
 597         <acronym>MAC</acronym> has been added.</para>
 598
 599       <para revision="282973" contrib="sponsor" sponsor="&ff;">The
 600         <literal>libgomp</literal> library is now only built when
 601         building <acronym>GCC</acronym> from the base system.  An
 602         up-to-date version is available in the Ports Collection as
 603         <filename
 604           role="package">devel/libiomp5-devel</filename>.</para>
 605
 606       <para revision="282988">The <filename>stdlib.h</filename> and
 607         <filename>malloc.h</filename> headers have been updated to
 608         make use of the <application>gcc</application>
 609         <literal>alloc_align()</literal> attribute.</para>
 610     </sect2>
 611
 612     <sect2 xml:id="userland-abi">
 613       <title>ABI Compatibility</title>
 614
 615       <para revision="271982">The &linux; compatibility version has
 616         been updated to <literal>2.6.18</literal>.  The
 617         <literal>compat.linux.osrelease</literal> &man.sysctl.8; is
 618         evaluated when building the <filename
 619           role="package">emulators/linux-c6</filename> and related
 620         ports.</para>
 621     </sect2>
 622   </sect1>
 623
 624   <sect1 xml:id="kernel">
 625     <title>Kernel</title>
 626
 627     <para>This section covers changes to kernel configurations, system
 628       tuning, and system control parameters that are not otherwise
 629       categorized.</para>
 630
 631     <sect2 xml:id="kernel-bugfix">
 632       <title>Kernel Bug Fixes</title>
 633
 634       <para revision="265876">A kernel bug that inhibited proper
 635         functionality of the <literal>dev.cpu.0.freq</literal>
 636         &man.sysctl.8; on &intel; processors with Turbo
 637         Boost&nbsp;&trade; enabled has been fixed.</para>
 638
 639       <para revision="271697" arch="powerpc">Support for
 640         &man.dtrace.1; stack tracing has been fixed for
 641         &os;/&arch.powerpc;, using the <literal>trapexit()</literal>
 642         and <literal>asttrapexit()</literal> functions instead of
 643         checking within addressed kernel space.</para>
 644
 645       <para revision="272089">A bug in &man.ipfw.4; that could
 646         potentially lead to a kernel panic when using &man.dummynet.4;
 647         at layer 2 has been fixed.</para>
 648
 649       <para revision="280930" contrib="sponsor" sponsor="&mitail;">The
 650         kernel <acronym>RPC</acronym> has been updated to include
 651         several enhancements:</para>
 652
 653       <itemizedlist>
 654         <listitem>
 655           <para>The 45 MiB limit on requests queued for
 656             &man.nfsd.8; threads has been removed.</para>
 657         </listitem>
 658
 659         <listitem>
 660           <para>Avoids unnecessary throttling by not deferring
 661             accounting for completed requests.</para>
 662         </listitem>
 663
 664         <listitem>
 665           <para>Fixes an integer overflow and signedness bugs.</para>
 666         </listitem>
 667       </itemizedlist>
 668
 669       <para revision="281261" arch="powerpc">Support for
 670         &man.dtrace.1; has been added for the
 671         Book-E&nbsp;&trade;.</para>
 672     </sect2>
 673
 674     <sect2 xml:id="kernel-config">
 675       <title>Kernel Configuration</title>
 676
 677       <para revision="266531">The <literal>IMAGACT_BINMISC</literal>
 678         kernel configuration option has been enabled by default,
 679         which enables application execution through emulators, such
 680         as <application>Qemu</application>.</para>
 681
 682       <para revision="268045">The <literal>VT</literal> kernel
 683         configuration file has been removed, and the &man.vt.4;
 684         driver is included in the <literal>GENERIC</literal> kernel.
 685         To enable &man.vt.4;, enter <literal>set kern.vty=vt</literal>
 686         at the &man.loader.8; prompt during boot, or add
 687         <literal>kern.vty=vt</literal> to &man.loader.conf.5; and
 688         reboot the system.</para>
 689
 690       <para revision="277904">The &man.config.8; utility has been
 691         updated to allow using a non-standard <filename
 692           class="directory">src/</filename> tree, specified as an
 693         argument to the <literal>-s</literal> flag.</para>
 694
 695       <para revision="277990" arch="powerpc64">The
 696         &os;/&arch.powerpc64; kernel now builds as
 697         a position-independent executable, allowing the kernel to be
 698         loaded into and run from any physical or virtual
 699         address.</para>
 700
 701       <important>
 702         <para>This change requires an update to &man.loader.8;.
 703           The userland and kernel must be updated before rebooting the
 704           system.</para>
 705       </important>
 706
 707       <para revision="279189" contrib="sponsor" sponsor="&ff;"
 708         arch="powerpc">Kernel support for Vector-Scalar eXtension
 709         (<acronym>VSX</acronym>) found on POWER7 and POWER8 hardware
 710         has been added.</para>
 711
 712       <para revision="279252" contrib="sponsor" sponsor="&ff;"
 713         arch="powerpc">The &man.pmap.9; implementation for 64-bit
 714         &powerpc; processors has been overhaulded to improve
 715         concurrency.</para>
 716
 717       <para revision="283959" contrib="sponsor"
 718         sponsor="&limelight;">A new kernel configuration option,
 719         <literal>EM_MULTIQUEUE</literal>, has been added which enables
 720         multi-queue support in the &man.em.4; driver.</para>
 721
 722       <note>
 723         <para>Multi-queue support in the &man.em.4; driver is not
 724           officially supported by &intel;.</para>
 725       </note>
 726     </sect2>
 727
 728     <sect2 xml:id="kernel-sysctl">
 729       <title>System Tuning and Controls</title>
 730
 731       <para revision="275140" contrib="sponsor" sponsor="&ff;">The
 732         &man.hwpmc.4; default and maximum callchain depths have been
 733         increased.  The default has been increased from 16 to 32, and
 734         the maximum increased from 32 to 128.</para>
 735
 736       <para revision="279361">The <literal>kern.osrelease</literal>
 737         and <literal>kern.osreldate</literal> are now configurable
 738         &man.jail.8; parameters.</para>
 739
 740       <para revision="280308,280949" contrib="sponsor"
 741         sponsor="&ix;, &ff;">The &man.devfs.5; device filesystem has
 742         been changed to update timestamps for read/write operations
 743         using seconds precision.  A new &man.sysctl.8;,
 744         <literal>vfs.devfs.dotimes</literal> has been added, which
 745         when set to a non-zero value, enables default precision
 746         timestamps for these operations.</para>
 747
 748       <para revision="282213" contrib="sponsor" sponsor="&ff;">A new
 749         &man.sysctl.8;, <literal>kern.racct.enable</literal>, has been
 750         added, which when set to a non-zero value allows using
 751         &man.rctl.8; with the <literal>GENERIC</literal> kernel.
 752         A new kernel configuration option,
 753         <literal>RACCT_DISABLED</literal> has also been added.</para>
 754
 755       <para revision="282901" contrib="sponsor" sponsor="&ff;">The
 756         <literal>GENERIC</literal> kernel configuration now includes
 757         <literal>RACCT</literal> and <literal>RCTL</literal> by
 758         default.</para>
 759
 760       <note>
 761         <para>To enable <literal>RACCT</literal> and
 762           <literal>RCTL</literal> on a system using the
 763           <literal>GENERIC</literal> kernel configuration, add
 764           <literal>kern.racct.enable=1</literal> to
 765           &man.loader.conf.5;, and reboot the system.</para>
 766       </note>
 767
 768       <para revision="283136" contrib="sponsor"
 769         sponsor="&limelight;">A new &man.sysctl.8;,
 770         <literal>net.inet.tcp.hostcache.purgenow</literal>, has
 771         been added, which when set to <literal>1</literal> during
 772         runtime will flush all
 773         <literal>net.inet.tcp.hostcache</literal> entries.</para>
 774     </sect2>
 775   </sect1>
 776
 777   <sect1 xml:id="drivers">
 778     <title>Devices and Drivers</title>
 779
 780     <para>This section covers changes and additions to devices and
 781       device drivers since &release.prev;.</para>
 782
 783     <sect2 xml:id="drivers-device">
 784       <title>Device Drivers</title>
 785
 786       <para revision="260903">Support for GPS ports has been added to
 787         &man.uhso.4;.</para>
 788
 789       <para revision="265132">The &man.full.4; device has been added,
 790         and the <literal>lindev(4)</literal> device has been removed.
 791         Prior to this change, <literal>lindev(4)</literal> provided
 792         only the <filename>/dev/full</filename> character device,
 793         returning <literal>ENOSPC</literal> on write attempts.  As
 794         this device is not specific to &linux;, a native &os; version
 795         has been added.</para>
 796
 797       <para revision="271705">Hardware context support has been
 798         added to the <literal>drm/i915</literal> driver, adding
 799         support for <application>Mesa</application> 9.2 and
 800         later.</para>
 801
 802       <para revision="273178">The &man.vt.4; driver has been updated,
 803         replacing the bitmapped <literal>kern.vt.spclkeys</literal>
 804         &man.sysctl.8; with individual
 805         <literal>kern.vt.kbd_*</literal> variants.</para>
 806
 807       <para revision="273598">The &man.hpet.4; driver has been updated
 808         to create a
 809         <filename>/dev/hpet<replaceable>N</replaceable></filename>
 810         device, providing access to <acronym>HPET</acronym> from
 811         userspace.</para>
 812
 813       <para revision="280183">The <literal>drm</literal> code has
 814         been updated to match &linux; version 3.8.13.</para>
 815
 816       <para revision="282783" arch="powerpc">Support for the Freescale
 817         <acronym>PCI</acronym> Root Complex device has been
 818         added.</para>
 819     </sect2>
 820
 821     <sect2 xml:id="drivers-storage">
 822       <title>Storage Drivers</title>
 823
 824       <para revision="265236" contrib="sponsor"
 825         sponsor="&lsi;, &spectralogic;" sponsorurl="">The &man.mpr.4;
 826         device has been added, providing support for LSI Fusion-MPT
 827         3 12Gb SCSI/SATA controllers.</para>
 828
 829       <para revision="265555" contrib="sponsor"
 830           sponsor="&lsi;">The &man.mrsas.4; driver has been added,
 831         providing support for LSI MegaRAID SAS controllers.  The
 832         &man.mfi.4; driver will attach to the controller, by default.
 833         To enable &man.mrsas.4; add
 834         <literal>hw.mfi.mrsas_enable=1</literal> to
 835         <filename>/boot/loader.conf</filename>, which turns off
 836         &man.mfi.4; device probing.</para>
 837
 838       <note>
 839         <para>At this time, the &man.mfiutil.8; utility and the &os;
 840           version of <application>MegaCLI</application> and
 841           <application>StorCli</application> do not work with
 842           &man.mrsas.4;.</para>
 843       </note>
 844
 845       <para revision="275461" contrib="sponsor" sponsor="&ix;">The
 846         &man.ctl.4; subsystem has been updated, increasing the ports
 847         limit from <literal>128</literal> to <literal>256</literal>,
 848         and <acronym>LUN</acronym> limit from <literal>256</literal>
 849         to <literal>1024</literal>.</para>
 850
 851       <para revision="276526">The <literal>asr(4)</literal> driver has
 852         been removed, and is no longer supported.</para>
 853
 854       <para revision="281387">The &man.hptnr.4; driver has been
 855         updated to version 1.1.1.</para>
 856     </sect2>
 857
 858     <sect2 xml:id="drivers-network">
 859       <title>Network Drivers</title>
 860
 861       <para revision="258830">Support for Broadcom chipsets BCM57764,
 862         BCM57767, BCM57782, BCM57786 and BCM57787 has been added to
 863         &man.bge.4;.</para>
 864
 865       <para revision="260448">Support for the &intel; Centrino&trade;
 866         Wireless-N 135 chipset has been added.</para>
 867
 868       <para revision="260552">Firmware for &intel; Centrino&trade;
 869         Wireless-N 105 devices has been added to the base
 870         system.</para>
 871
 872       <para revision="261975">The deprecated nve(4) driver has been
 873         removed.  Users of NVIDIA nForce MCP network adapters are
 874         advised to use the &man.nfe.4; driver instead, which has been
 875         the default driver for this hardware since
 876         &os;&nbsp;7.0.</para>
 877
 878       <para revision="264601" contrib="sponsor"
 879         sponsor="&darpa_afrl;">The <literal>if_nf10bmac(4)</literal>
 880         device has been added, providing support for NetFPGA-10G
 881         Embedded CPU Ethernet Core.</para>
 882
 883       <note>
 884         <para>The <literal>if_nf10bmac(4)</literal> driver operates on
 885           the FPGA, and is not suited for the PCI host
 886           interface.</para>
 887       </note>
 888
 889       <para revision="265348" contrib="sponsor"
 890         sponsor="&netgate;">The &man.ath.hal.4; driver has been
 891         updated to support the Atheros AR1111 chipset.</para>
 892
 893       <para revision="266770">Support for the &intel; Centrino&trade;
 894         Wireless-N 105 chipset has been added.</para>
 895
 896       <para revision="266757" contrib="sponsor"
 897         sponsor="&chelsio;">Support for the &man.cxgbe.4; Terminator
 898         5 (T5) 10G/40G cards has been added to &man.netmap.4;.</para>
 899
 900       <para revision="272730">The &man.alc.4; driver has been updated
 901         to support AR816x and AR817x ethernet controllers.</para>
 902
 903       <para revision="273331">The &man.vxlan.4; driver has been added,
 904         which creates a virtual Layer 2 (Ethernet) network overlaid in
 905         a Layer 3 (IP/UDP) network.  The &man.vxlan.4; driver is
 906         analogous to &man.vlan.4;, but is designed to be better suited
 907         for large, multiple-tenant datacenter environments.</para>
 908
 909       <para revision="274246" contrib="sponsor" sponsor="&yandex;">The
 910         &man.gre.4; driver has been significantly overhauled, and has
 911         been split into two separate modules, &man.gre.4; and
 912         &man.me.4;.</para>
 913
 914       <para revision="283766" contrib="sponsor"
 915         sponsor="&limelight;">The &man.em.4; driver has been updated
 916         with improved transmission queue hang detection.</para>
 917     </sect2>
 918   </sect1>
 919
 920   <sect1 xml:id="hardware">
 921     <title>Hardware Support</title>
 922
 923     <para>This section covers general hardware support for physical
 924       machines, hypervisors, and virtualization environments, as well
 925       as hardware changes and updates that do not otherwise fit in
 926       other sections of this document.</para>
 927
 928     <sect2 xml:id="hardware-support">
 929       <title>Hardware Support</title>
 930
 931       <para revision="268303">The &man.asmc.4; driver has been
 932         updated to support the &apple;&nbsp;MacMini 3,1.</para>
 933
 934       <para revision="268351">Support for &os;/ia64 has been dropped
 935         as of &os;&nbsp;11.</para>
 936
 937       <para revision="274386">An issue that could cause a system to
 938         hang when entering <acronym>ACPI</acronym>
 939         <literal>S3</literal> state (suspend to
 940         <acronym>RAM</acronym>) has been corrected in the &man.acpi.4;
 941         and &man.pci.4; drivers.</para>
 942
 943       <para revision="274733" arch="powerpc">The power management unit
 944         subsystem has been updated to support power button events on
 945         certain &arch.powerpc; hardware, such as aluminum
 946         PowerBook&nbsp;&reg;.</para>
 947
 948       <para revision="275171,275190" arch="powerpc">The &man.hwpmc.4;
 949         driver has been updated to correct performance counter
 950         sampling on G4 (MPC74xxx) and G5 class processors.</para>
 951
 952       <para revision="281713" arch="powerpc">The &man.hwpmc.4;
 953         driver has been updated to support the Freescale e500
 954         core.</para>
 955
 956       <para revision="275732" contrib="sponsor"
 957         sponsor="&ff;,&netgate;">The
 958         <application>OpenCrypto</application> framework has been
 959         updated to include <literal>AES-ICM</literal> and
 960         <literal>AES-GCM</literal> modes, both of which have also been
 961         added to the &man.aesni.4; driver.</para>
 962
 963       <para revision="283766">The &man.ig4.4; driver has been added,
 964         providing support for the fourth generation &intel;
 965         <acronym>I2C</acronym> SMBus.</para>
 966     </sect2>
 967
 968     <sect2 xml:id="hardware-virtualization">
 969       <title>Virtualization Support</title>
 970
 971       <para revision="260410">Support for the <quote>Virtual Interrupt
 972           Delivery</quote> feature of &intel;&nbsp;VT-x is enabled if
 973         supported by the CPU.  This feature can be disabled by running
 974         <literal>sysctl hw.vmm.vmx.use_apic_vid=0</literal>.
 975         Additionally, to persist this setting across reboots, add
 976         <literal>hw.vmm.vmx.use_apic_vid=0</literal> to
 977         <filename>/etc/sysctl.conf</filename>.</para>
 978
 979       <para revision="260532">Support for <quote>Posted Interrupt
 980           Processing</quote> is enabled if supported by the CPU.  This
 981         feature can be disabled by running <literal>sysctl
 982           hw.vmm.vmx.use_apic_pir=0</literal>.  Additionally, to
 983         persist this setting across reboots, add
 984         <literal>hw.vmm.vmx.use_apic_pir=0</literal> to
 985         <filename>/etc/sysctl.conf</filename>.</para>
 986
 987       <para revision="260582">Unmapped IO support has been added to
 988         &man.virtio_blk.4;.</para>
 989
 990       <para revision="260583">Unmapped IO support has been added to
 991         &man.virtio_scsi.4;.</para>
 992
 993       <para revision="260847">The &man.virtio_random.4; driver has
 994         been added to harvest entropy from the host system.</para>
 995
 996       <para revision="261504">&os;/&arch.i386; guests can be run under
 997         bhyve.</para>
 998
 999       <para revision="267536" contrib="sponsor"
1000         sponsor="&citrix.rd;">Support for running a &os;/&arch.amd64;
1001         <application>Xen</application> guest instance as
1002         <acronym>PVH</acronym> guest has been added.
1003         <acronym>PVH</acronym> mode, short for <quote>Para-Virtualized
1004           Hardware</quote>, uses para-virtualized drivers for boot and
1005         I/O, and uses hardware virtualization extensions for all other
1006         tasks, without the need for emulation.</para>
1007
1008       <para revision="273515">The &man.virtio.console.4; driver has
1009         been added, which provides an interface to VirtIO console
1010         devices through a &man.tty.4; device.</para>
1011
1012       <para revision="279957">The &man.bhyve.8; hypervisor has been
1013         updated to support <literal>DSM TRIM</literal> commands for
1014         virtual <acronym>AHCI</acronym> disks.</para>
1015
1016       <para revision="281439" arch="arm">Support for the
1017         <application>QEMU</application> <literal>virt</literal> system
1018         has been added.</para>
1019
1020       <para revision="282212" contrib="sponsor" sponsor="&msostc;">The
1021         HyperV&trade; drivers have been updated with several
1022         enhancements:</para>
1023
1024       <itemizedlist>
1025         <listitem>
1026           <para>The &man.hv.vmbus.4; driver now has multi-channel
1027             support.</para>
1028         </listitem>
1029
1030         <listitem>
1031           <para>The &man.hv.storvsc.4; driver now has scatter/gather
1032             support, in addition to performance improvements.</para>
1033         </listitem>
1034
1035         <listitem>
1036           <para>The &man.hv.kvp.4; driver has received several bug
1037             fixes.</para>
1038         </listitem>
1039       </itemizedlist>
1040
1041       <para revision="282274">Support for &man.xen.4; para-virtualized
1042         <literal>domU</literal> kernels has been removed.</para>
1043     </sect2>
1044
1045     <sect2 xml:id="hardware-arm">
1046       <title>ARM Support</title>
1047
1048       <para revision="260921">The &man.nand.4; device is enabled for
1049         ARM devices by default.</para>
1050
1051       <para revision="273264" arch="armv6">An issue that could cause
1052         instability when detecting <acronym>SD</acronym> cards on the
1053         Raspberry Pi <acronym>SOC</acronym> has been fixed.</para>
1054
1055       <para revision="275963">The <literal>bcm2835_cpufreq</literal>
1056         driver has been added, which supports <acronym>CPU</acronym>
1057         frequency and voltage control on the Raspberry Pi
1058         <acronym>SOC</acronym>.</para>
1059
1060       <para revision="280259" contrib="sponsor" sponsor="&ff;">Initial
1061         support for the ARM AArch64 architecture has been
1062         added.</para>
1063
1064       <para revision="282779" arch="arm">Kernel support for Thumb-2
1065         has been added.</para>
1066
1067       <para revision="282827">Support for the hardware power button
1068         on the BeagleBone Black system has been added.</para>
1069
1070       <para revision="284273" contrib="sponsor"
1071         sponsor="&ff;">Initial
1072         <acronym>ACPI</acronym> support has been added for
1073         &os;/&arch.arm64;.</para>
1074     </sect2>
1075   </sect1>
1076
1077   <sect1 xml:id="storage">
1078     <title>Storage</title>
1079
1080     <para>This section covers changes and additions to file systems
1081       and other storage subsystems, both local and networked.</para>
1082
1083     <sect2 xml:id="storage-general">
1084       <title>General Storage</title>
1085
1086       <para revision="278037" contrib="sponsor" sponsor="&ix;">The
1087         &man.ctl.4; <acronym>LUN</acronym> mapping has been rewritten,
1088         replacing <acronym>iSCSI</acronym>-specific mapping mechanisms
1089         with a new mechanism that works for any port.</para>
1090
1091       <para revision="278354" contrib="sponsor" sponsor="&ix;">The
1092         &man.ctld.8; utility has been updated to allow controlling
1093         non-<acronym>iSCSI</acronym> &man.ctl.4; ports.</para>
1094     </sect2>
1095
1096     <sect2 xml:id="storage-net">
1097       <title>Networked Storage</title>
1098
1099       <para revision="270096" contrib="sponsor" sponsor="&ff;">The new
1100         filesystem automount facility, &man.autofs.5;, has been added.
1101         The new &man.autofs.5; facility is similar to that found in
1102         other &unix;-like operating systems, such as OS&nbsp;X&trade;
1103         and Solaris&trade;.  The &man.autofs.5; facility uses
1104         a &sun;-compatible &man.auto.master.5; configuration file, and
1105         is administered with the &man.automount.8; userland utility,
1106         and the &man.automountd.8; and &man.autounmountd.8;
1107         daemons.</para>
1108     </sect2>
1109
1110     <sect2 xml:id="storage-zfs">
1111       <title>ZFS</title>
1112
1113       <para revision="275748">The <literal>arc_meta_limit</literal>
1114         statistics are now visible through the
1115         <literal>kstat</literal> &man.sysctl.8;.  As a result of this
1116         change, the <literal>vfs.zfs.arc_meta_used</literal>
1117         &man.sysctl.8; has been removed, and replaced with the
1118         <literal>kstat.zfs.misc.arcstats.arc_meta_used</literal>
1119         &man.sysctl.8;.</para>
1120     </sect2>
1121
1122     <sect2 xml:id="storage-geom">
1123       <title>&man.geom.4;</title>
1124
1125       <para revision="267359">Support for the
1126         <literal>disklabel64</literal> partitioning scheme has been
1127         added to &man.gpart.8;.</para>
1128     </sect2>
1129   </sect1>
1130
1131   <sect1 xml:id="boot">
1132     <title>Boot Loader Changes</title>
1133
1134     <para>This section covers the boot loader, boot menu, and other
1135       boot-related changes.</para>
1136
1137     <sect2 xml:id="boot-loader">
1138       <title>Boot Loader Changes</title>
1139
1140       <para revision="274085">The &man.vt.4; driver has been made the
1141         default system console driver.  The &man.syscons.4; driver is
1142         still available, and can be enabled by adding
1143         <literal>kern.vty=sc</literal> in &man.loader.conf.5;.
1144         Alternatively, &man.syscons.4; can be enabled at boot time by
1145         entering <literal>set kern.vty=sc</literal> at the
1146         &man.loader.8; prompt.</para>
1147
1148       <para revision="281616">The boot loader has been updated to
1149         support entering the <acronym>GELI</acronym> passphrase before
1150         loading the kernel.  To enable this behavior, add
1151         <literal>geom_eli_passphrase_prompt="YES"</literal> to
1152         &man.loader.conf.5;.</para>
1153     </sect2>
1154
1155     <sect2 xml:id="boot-menu">
1156       <title>Boot Menu Changes</title>
1157
1158       <para>&nbsp;</para>
1159     </sect2>
1160   </sect1>
1161
1162   <sect1 xml:id="network">
1163     <title>Networking</title>
1164
1165     <para>This section describes changes that affect networking in
1166       &os;.</para>
1167
1168     <sect2 xml:id="network-protocols">
1169       <title>Network Procols</title>
1170
1171       <para revision="263140">Support for the IPX network transport
1172         protocol has been removed, and will not be supported in
1173         &os;&nbsp;11 and later releases.</para>
1174
1175       <para revision="272720" contrib="sponsor"
1176         sponsor="&limelight;">Support for <acronym>PLPMTUD</acronym>
1177         blackhole detection (<acronym>RFC</acronym> 4821) has been
1178         added to the &man.tcp.4; stack, disabled by default.  New
1179         control tunables have been added:</para>
1180
1181       <informaltable frame="none" pgwide="0">
1182         <tgroup cols="2">
1183           <colspec colwidth="1*"/>
1184           <colspec colwidth="1*"/>
1185           <thead>
1186             <row>
1187               <entry>Tunable</entry>
1188               <entry>Description</entry>
1189             </row>
1190           </thead>
1191
1192           <tbody>
1193             <row>
1194               <entry><literal>net.inet.tcp.pmtud_blackhole_detection</literal></entry>
1195               <entry>Enables or disables <acronym>PLPMTUD</acronym>
1196                 blackhole detection</entry>
1197             </row>
1198
1199             <row>
1200               <entry><literal>net.inet.tcp.pmtud_blackhole_mss</literal></entry>
1201               <entry><acronym>MSS</acronym> to try for IPv4</entry>
1202             </row>
1203
1204             <row>
1205               <entry><literal>net.inet.tcp.v6pmtud_blackhole_mss</literal></entry>
1206               <entry><acronym>MSS to try for IPv6</acronym></entry>
1207             </row>
1208           </tbody>
1209         </tgroup>
1210       </informaltable>
1211
1212       <para>New monitoring &man.sysctl.8;s haven been added:</para>
1213
1214       <informaltable frame="none" pgwide="0">
1215         <tgroup cols="2">
1216           <colspec colwidth="1*"/>
1217           <colspec colwidth="1*"/>
1218           <thead>
1219             <row>
1220               <entry>Tunable</entry>
1221               <entry>Description</entry>
1222             </row>
1223           </thead>
1224
1225           <tbody>
1226             <row>
1227               <entry><literal>net.inet.tcp.pmtud_blackhole_activated</literal></entry>
1228               <entry>Number of times the code was activated to attempt
1229                 downshifting the <acronym>MSS</acronym></entry>
1230             </row>
1231
1232             <row>
1233               <entry><literal>net.inet.tcp.pmtud_blackhole_min_activated</literal></entry>
1234               <entry>Number of times the blackhole
1235                 <acronym>MSS</acronym> was used in an attempt to
1236                 downshift</entry>
1237             </row>
1238
1239             <row>
1240               <entry><literal>net.inet.tcp.pmtud_blackhole_failed</literal></entry>
1241               <entry>Number of times that the blackhole failed to
1242                 connect after downshifting the
1243                 <acronym>MSS</acronym></entry>
1244             </row>
1245           </tbody>
1246         </tgroup>
1247       </informaltable>
1248
1249       <para revision="280971" contrib="sponsor"
1250         sponsor="&netflix;, &nginx;">Support for <acronym>IP</acronym>
1251         identification for atomic datagrams (<acronym>RFC</acronym>
1252         6864) has been added.  Support for this feature can be toggled
1253         with the <literal>net.inet.ip.rfc6864</literal>
1254         &man.sysctl.8;, which is enabled by default.</para>
1255     </sect2>
1256   </sect1>
1257
1258   <sect1 xml:id="ports">
1259     <title>Ports Collection and Package Infrastructure</title>
1260
1261     <para>This section covers changes to the &os;&nbsp;Ports
1262       Collection, package infrastructure, and package maintenance and
1263       installation tools.</para>
1264
1265     <sect2 xml:id="ports-infrastructure">
1266       <title>Infrastructure Changes</title>
1267
1268       <para>&nbsp;</para>
1269     </sect2>
1270
1271     <sect2 xml:id="ports-packages ">
1272       <title>Packaging Changes</title>
1273
1274       <para>&nbsp;</para>
1275     </sect2>
1276   </sect1>
1277
1278   <sect1 xml:id="doc">
1279     <title>Documentation</title>
1280
1281     <para>This section covers changes to the &os;&nbsp;Documentation
1282       Project sources and toolchain.</para>
1283
1284     <sect2 xml:id="doc-sources">
1285       <title>Documentation Source Changes</title>
1286
1287       <para>&nbsp;</para>
1288     </sect2>
1289
1290     <sect2 xml:id="doc-toolchain">
1291       <title>Documentation Toolchain Changes</title>
1292
1293       <para>&nbsp;</para>
1294     </sect2>
1295   </sect1>
1296
1297   <sect1 xml:id="releng">
1298     <title>Release Engineering and Integration</title>
1299
1300     <para>This section convers changes that are specific to the
1301       &os;&nbsp;Release Engineering processes.</para>
1302
1303     <sect2 xml:id="releng-changes">
1304       <title>Integration Changes</title>
1305
1306       <para revision="277458" contrib="sponsor" sponsor="&ff;">The
1307         Release Engineering build tools have been updated to include
1308         support for producing virtual machine disk images for various
1309         cloud hosting providers.</para>
1310
1311       <para revision="278926">The Release Engineering build tools have
1312         been updated to use multi-threaded &man.xz.1;.  By default,
1313         the number of &man.xz.1; threads is set to the number of cores
1314         available.</para>
1315
1316       <para revision="281802" contrib="sponsor" sponsor="&ff;">The
1317         Release Engineering build tools have been updated to include
1318         support for building &os;/&arch.arm64; virtual machine and
1319         memory stick installation images.</para>
1320     </sect2>
1321   </sect1>
1322 </article>