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+++ b/erts/doc/src/notes.xml
@@ -2078,6 +2078,2015 @@
</section>
+<section><title>Erts 10.3.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed more bugs in <c>process_info(reductions)</c>
+ causing it to sometimes behave non-monotonic. That is, a
+ subsequent call toward the same process could return a
+ lower reduction value.</p>
+ <p>
+ Own Id: OTP-15793 Aux Id: ERIERL-337, OTP-15709 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.3.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Add missing documentation of new external tags
+ <c>NEW_PID</c>, <c>NEW_PORT</c> and
+ <c>NEWER_REFERENCE</c> introduced in OTP 19.</p> <p>These
+ new tags are planned to be "activated" in OTP 23 when
+ distribution capability flag <c>DFLAG_BIG_CREATION</c>
+ becomes mandatory. Older nodes (>= 19) are able to decode
+ these new tags and send them back to the new node. Nodes
+ older than OTP 23 will however never encode their own
+ local pids, ports and references using the new tags.</p>
+ <p>
+ Own Id: OTP-15766</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.3.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix <c>erlang:open_port/2</c> with the <c>fd</c> option
+ to correctly cleanup the pollset when the port is closed.
+ Before this fix there would be error printouts sent to
+ logger when the same fd was reused in a new port.</p>
+ <p>
+ Own Id: OTP-15753 Aux Id: ERL-900 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.3.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a bug in <c>seq_trace:reset_trace/0</c> that
+ could crash the emulator.</p>
+ <p>
+ Own Id: OTP-15704</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>process_info(reductions)</c> causing it
+ to sometimes return invalid results.</p>
+ <p>
+ Own Id: OTP-15709 Aux Id: ERIERL-337 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.3.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>If a suspend/resume signal pair was sent to a process
+ while it was executing dirty, the receiving process could
+ later end up in a suspended state indefinitely. This bug
+ was introduced in ERTS version 10.0 (OTP 21.0).</p>
+ <p>Suspend/resume signals are sent from <seealso
+ marker="erts:erlang#suspend_process/1"><c>erlang:suspend_process()</c></seealso>/<seealso
+ marker="erts:erlang#resume_process/1"><c>erlang:resume_process()</c></seealso>.
+ The <seealso
+ marker="runtime_tools:dbg"><c>dbg</c></seealso> trace
+ tool utilize this functionality and could thus trigger
+ this bug.</p>
+ <p>
+ Own Id: OTP-15688</p>
+ </item>
+ <item>
+ <p>
+ Fix a possible deadlock when terminating the ERTS caused
+ by a dirty scheduler not releasing it's run-queue lock
+ when terminating.</p>
+ <p>
+ Own Id: OTP-15690 Aux Id: PR-2172 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>When multiplying a number by itself, a word beyond the
+ number on the heap could be read (and ignored). This bug
+ was extremely unlikely to actually cause a real
+ problem.</p>
+ <p>
+ Own Id: OTP-15484</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where doing <c>seq_trace:reset_trace()</c> while
+ another process was doing a garbage collection could
+ cause the run-time system to segfault.</p>
+ <p>
+ Own Id: OTP-15490</p>
+ </item>
+ <item>
+ <p>
+ Fix reading of ancillary data from packet oriented
+ sockets on old Linux kernel versions. Without this fix,
+ getting the data would cause the port to enter an
+ infinite loop.</p>
+ <p>
+ Own Id: OTP-15494</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where crash dumping or doing
+ <c>erlang:system_info(procs)</c> while another process
+ was doing a garbage collection could cause the run-time
+ system to segfault.</p>
+ <p>
+ Own Id: OTP-15527</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>erlang:system_info(kernel_poll)</c> to return
+ correct value. Before this fix, the call always returned
+ <c>false</c>.</p>
+ <p>
+ Own Id: OTP-15556</p>
+ </item>
+ <item>
+ <p>
+ Fix bug in <c>enif_make_map_from_arrays</c> that would
+ produce broken maps when number of keys were 32. Bug
+ exists since OTP 21.0.</p>
+ <p>
+ Own Id: OTP-15567</p>
+ </item>
+ <item>
+ <p>
+ Fix a bug in <c>binary:encode_unsigned</c> that may cause
+ a read of uninitialized memory.</p>
+ <p>
+ The bug existed since the function was added (OTP
+ R16B02).</p>
+ <p>
+ Own Id: OTP-15583 Aux Id: PR-2118 </p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug that could cause <c>heart</c> to kill an
+ exiting node before it had time to flush all buffered
+ writes. If environment variable
+ <c>HEART_KILL_SIGNAL=SIGABRT</c> was set a superfluous
+ core dump could also be generated.</p>
+ <p>
+ Own Id: OTP-15599 Aux Id: ERIERL-298 </p>
+ </item>
+ <item>
+ <p>
+ Fix <c>enif_consume_timeslice</c> to be a no-op on dirty
+ scheduler and not crash debug compiled emulator.</p>
+ <p>
+ Own Id: OTP-15604</p>
+ </item>
+ <item>
+ <p>
+ Fixed macro redefinition warnings.</p>
+ <p>
+ Own Id: OTP-15629</p>
+ </item>
+ <item>
+ <p>
+ <c>to_erl</c> fixed to not garble terminal input beyond
+ 7-bit ASCII.</p>
+ <p>
+ Own Id: OTP-15650 Aux Id: ERL-854, PR-2161 </p>
+ </item>
+ <item>
+ <p>
+ Minor fixes for <c>make clean</c>.</p>
+ <p>
+ Own Id: OTP-15657</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug in all <c>ets:select*</c> and
+ <c>ets:match*</c> functions that could in some rare cases
+ lead to very poor performance.</p>
+ <p>
+ Own Id: OTP-15660 Aux Id: ERL-869 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Add <c>erlang:system_flag(system_logger, Pid)</c> and
+ <c>erlang:system_info(system_logger)</c>. This
+ system_flag can be used to set the process that will
+ receive the logging messages generated by ERTS.</p>
+ <p>
+ Own Id: OTP-15375</p>
+ </item>
+ <item>
+ <p><c>integer_to_list/2</c> and
+ <c>integer_to_binary/2</c> are now implemented in C,
+ improving their performance.</p>
+ <p>
+ Own Id: OTP-15503 Aux Id: PR-2052 </p>
+ </item>
+ <item>
+ <p>
+ Improved <c>term_to_binary</c> to do more fair reduction
+ count and yielding when encoding large byte lists
+ (strings).</p>
+ <p>
+ Own Id: OTP-15514 Aux Id: ERL-774 </p>
+ </item>
+ <item>
+ <p>
+ Made internal port drivers more robust against
+ <c>erlang:port_control</c> with invalid arguments and
+ added documentation warnings about such abuse.</p>
+ <p>
+ Own Id: OTP-15555 Aux Id: ERIERL-231 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug on NetBSD where the <c>exit_status</c> from a
+ port program would never be sent.</p>
+ <p>
+ Own Id: OTP-15558 Aux Id: ERL-725 </p>
+ </item>
+ <item>
+ <p>There is a new function <c>persistent:term(Key,
+ Default)</c> to allow specifying a default when looking
+ up a persistent term.</p>
+ <p>
+ Own Id: OTP-15576 Aux Id: ERL-843 </p>
+ </item>
+ <item>
+ <p>A transitory emulator option '<c>+ztma true</c>' has
+ been added to allow running existing BEAM code that
+ relies on "tuple calls" (dispatch on parameterized
+ modules) which has been compiled under OTP 20 or earlier.
+ This option will be removed in OTP 22, so such modules
+ should eventually be recompiled with the
+ <c>+tuple_calls</c> option.</p>
+ <p>
+ Own Id: OTP-15580 Aux Id: PR-2113 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixes of install/release phase in build system.</p>
+ <list> <item>The source tree was modified when
+ installing/releasing and/or applying a patch.</item>
+ <item>Some files were installed with wrong access
+ rights.</item> <item>If applying a patch (using
+ <c>otp_patch_apply</c>) as another user (except root)
+ than the user that built the source, the documentation
+ was not properly updated.</item> </list>
+ <p>
+ Own Id: OTP-15551</p>
+ </item>
+ <item>
+ <p>
+ Setting the <c>recbuf</c> size of an inet socket the
+ <c>buffer</c> is also automatically increased. Fix a bug
+ where the auto adjustment of inet buffer size would be
+ triggered even if an explicit inet buffer size had
+ already been set.</p>
+ <p>
+ Own Id: OTP-15651 Aux Id: ERIERL-304 </p>
+ </item>
+ <item>
+ <p>
+ Reading from UDP using active <c>true</c> or active
+ <c>N</c> mode has been optimized when more packets than
+ specified by <c>read_packets</c> are available on the
+ socket.</p>
+ <p>
+ Own Id: OTP-15652 Aux Id: ERIERL-304 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ When using the <c>{linger,{true,T}}</c> option;
+ <c>gen_tcp:listen/2</c> used the full linger time before
+ returning for example <c>eaddrinuse</c>. This bug has now
+ been corrected.</p>
+ <p>
+ Own Id: OTP-14728 Aux Id: ERIERL-303 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix bug where doing a <c>gen_tcp:send</c> on a socket
+ with <c>delay_send</c> set to true could cause a segfault
+ if the other side closes the connection.</p>
+ <p>
+ Bug was introduced in erts-10.2 (OTP-21.2).</p>
+ <p>
+ Own Id: OTP-15536 Aux Id: ERL-827 </p>
+ </item>
+ <item>
+ <p>
+ Fix a race condition when a port program closes that
+ could result in the next started port to hang during
+ startup.</p>
+ <p>
+ When this fault happens the following error is normally
+ (but not always) logged:</p>
+ <p>
+ <c> =ERROR REPORT==== 14-Jan-2019::10:45:52.868246
+ ===</c><br/><c> Bad input fd in erts_poll()! fd=11,
+ port=#Port&lt;0.505>, driver=spawn, name=/bin/sh -s
+ unix:cmd </c></p>
+ <p>
+ Bug was introduced in erts-10.0 (OTP-21.0).</p>
+ <p>
+ Own Id: OTP-15537</p>
+ </item>
+ <item>
+ <p>
+ Fix a bug where polling for external events could be
+ delayed for a very long time if all active schedulers
+ were 100% loaded.</p>
+ <p>
+ Bug was introduced in erts-10.2 (OTP-21.2).</p>
+ <p>
+ Own Id: OTP-15538 Aux Id: ERIERL-229 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a crash when dangling files were closed after
+ <c>init:restart/0</c>.</p>
+ <p>
+ Own Id: OTP-15495 Aux Id: ERL-821 </p>
+ </item>
+ <item>
+ <p>
+ A bug that could cause dirty schedulers to become
+ unresponsive has been fixed.</p>
+ <p>
+ Own Id: OTP-15509 Aux Id: PR-2027, PR-2093 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug on big endian architectures when changing file
+ permissions or ownership with <c>file:change_mode</c>,
+ <c>change_owner</c>, <c>change_group</c> or
+ <c>write_file_info</c>. Bug exists since OTP-21.0.</p>
+ <p>
+ Own Id: OTP-15485</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>atomics</c> with option
+ <c>{signed,false}</c> when returned values are <c>(1 bsl
+ 63)</c> or larger. Could cause heap corruption leading to
+ VM crash or other unpleasant symptoms. Bug exists since
+ OTP-21.2 when module <c>atomics</c> was introduced.</p>
+ <p>
+ Own Id: OTP-15486 Aux Id: PR-2061 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in operator <c>band</c> of two negative
+ operands causing erroneous result if the absolute value
+ of one of the operands have the lowest <c>N*W</c> bits as
+ zero and the other absolute value is not larger than
+ <c>N*W</c> bits. <c>N</c> is an integer of 1 or larger
+ and <c>W</c> is 32 or 64 depending on word size.</p>
+ <p>
+ Own Id: OTP-15487 Aux Id: ERL-804 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ When a process was waiting for a TCP socket send
+ operation to complete, and another process closed the
+ socket during that send, the sending process could hang.
+ This bug has now been corrected.</p>
+ <p>
+ Own Id: OTP-12242 Aux Id: ERL-561 </p>
+ </item>
+ <item>
+ <p>
+ Document <c>bit_size</c> in match specifications and
+ allow it in <c>ets:fun2ms</c>.</p>
+ <p>
+ Own Id: OTP-15343 Aux Id: PR-1962 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>ets:select_replace</c> when called with a
+ fully bound key could cause a following call to
+ <c>ets:next</c> or <c>ets:prev</c> to crash the emulator
+ or return invalid result.</p>
+ <p>
+ Own Id: OTP-15346</p>
+ </item>
+ <item>
+ <p>When a module has been purged from memory, any
+ literals belonging to that module will be copied to all
+ processes that hold references to them. The max heap size
+ limit would be ignored in the garbage collection
+ initiated when copying literals to a process. If the max
+ heap size was exceeded, the process would typically be
+ terminated in the following garbage collection. Corrected
+ to terminate the process directly if copying a literal
+ would exceed the max heap size.</p>
+ <p>
+ Own Id: OTP-15360</p>
+ </item>
+ <item>
+ <p>
+ Fix compilation of run_erl on Solaris 11.4 and later.</p>
+ <p>
+ Own Id: OTP-15389</p>
+ </item>
+ <item>
+ <p>Fixed a bug where <c>lists:reverse/1-2</c> could use
+ far too many reductions. This bug was introduced in
+ <c>OTP 21.1</c>.</p>
+ <p>
+ Own Id: OTP-15436</p>
+ </item>
+ <item>
+ <p>Fixed a bug where a dirty scheduler could stay awake
+ forever if a distribution entry was removed as part of a
+ dirty GC.</p>
+ <p>
+ Own Id: OTP-15446 Aux Id: PR-2024 </p>
+ </item>
+ <item>
+ <p>
+ Fix microstate accounting handing in various places. Most
+ importantly the GC states when the GC is run on a dirty
+ scheduler are now managed correctly.</p>
+ <p>
+ Own Id: OTP-15450 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>file:sendfile</c> when the send operation
+ failed. For sockets in <c>active</c> modes it could cause
+ emulator crash or a hanging call. For sockets with
+ <c>{active,false}</c> an unexpected <c>{inet_reply, _,
+ _}</c> message could be sent to the calling process. The
+ bug exists since OTP-21.0.</p>
+ <p>
+ Own Id: OTP-15461 Aux Id: ERL-784 </p>
+ </item>
+ <item>
+ <p>
+ The erts configure script has been updated to reject any
+ CFLAGS that does not have <c>-O</c>. This in order to
+ prevent the common mistake of forgetting to add
+ <c>-O2</c> to custom CFLAGS.</p>
+ <p>
+ Own Id: OTP-15465</p>
+ </item>
+ <item>
+ <p>
+ Fix reduction count in lists:member/2</p>
+ <p>
+ Own Id: OTP-15474 Aux Id: ERIERL-229 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ New <c>counters</c> and <c>atomics</c> modules supplies
+ access to highly efficient operations on mutable fixed
+ word sized variables.</p>
+ <p>
+ Own Id: OTP-13468</p>
+ </item>
+ <item>
+ <p>There is a new module <c>persistent_term</c> that
+ implements a term storage suitable for terms that are
+ frequently used but never or infrequently updated.
+ Lookups are done in constant time without copying the
+ terms.</p>
+ <p>
+ Own Id: OTP-14669 Aux Id: PR-1989 </p>
+ </item>
+ <item>
+ <p>
+ A function <c>inet:getifaddrs/1</c> that takes a list
+ with a namespace option has been added, for platforms
+ that support that feature, for example Linux (only?).</p>
+ <p>
+ Own Id: OTP-15121 Aux Id: ERIERL-189, PR-1974 </p>
+ </item>
+ <item>
+ <p>Added the <c>nopush</c> option for TCP sockets, which
+ corresponds to <c>TCP_NOPUSH</c> on *BSD and
+ <c>TCP_CORK</c> on Linux.</p>
+ <p>This is also used internally in <c>file:sendfile</c>
+ to reduce latency on subsequent send operations.</p>
+ <p>
+ Own Id: OTP-15357 Aux Id: ERL-698 </p>
+ </item>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ <item>
+ <p>
+ Optimize handling of send_delay for tcp sockes to better
+ work with the new pollthread implementation introduced in
+ OTP-21.</p>
+ <p>
+ Own Id: OTP-15471 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Optimize driver_set_timer with a zero timeout to
+ short-circuit and not create any timer structure, but
+ instead schedule the timer immediately.</p>
+ <p>
+ Own Id: OTP-15472 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Add <c>erl_xcomp_code_model_small</c> as a cross
+ configure variable in order to let the emulator be build
+ with the assumption that a small code model will be used
+ on the target machine.</p>
+ <p>
+ Own Id: OTP-15473 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Add a new pollset that is made to handle sockets that use
+ <c>{active, true}</c> or <c>{active, N}</c>. The new
+ pollset will not be polled by a pollthread, but instead
+ polled by a normal scheduler.</p>
+ <p>
+ This change was made because of the overhead associated
+ with constantly having to re-apply the ONESHOT mechanism
+ on fds that all input events were interesting.</p>
+ <p>
+ The new pollset is only active on platforms that support
+ concurrent kernel poll updates, i.e. Linux and BSD.</p>
+ <p>
+ Own Id: OTP-15475 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug where emulator would segfault if a literal
+ message was sent when sequence tracing was enabled.</p>
+ <p>
+ Own Id: OTP-15478 Aux Id: ERL-741 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.3</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>Added an optional <c>./configure</c> flag to compile
+ the emulator with spectre mitigation:
+ <c>--with-spectre-mitigation</c></p>
+ <p>Note that this requires a recent version of GCC with
+ support for spectre mitigation and the
+ <c>--mindirect-branch=thunk</c> flag, such as
+ <c>8.1</c>.</p>
+ <p>
+ Own Id: OTP-15430 Aux Id: ERIERL-237 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a rare bug where files could be closed on a
+ normal instead of an IO scheduler, resulting in system
+ instability if the operation blocked.</p>
+ <p>
+ Own Id: OTP-15421</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A bug where the socket option 'pktoptions' caused a read
+ of uninitialized memory has been fixed. Would cause
+ malfunction on FreeBSD.</p>
+ <p>
+ Own Id: OTP-14297 Aux Id: OTP-15141 </p>
+ </item>
+ <item>
+ <p>Fixed a memory leak on errors when reading files.</p>
+ <p>
+ Own Id: OTP-15318</p>
+ </item>
+ <item>
+ <p>File access through UNC paths works again on Windows.
+ This regression was introduced in OTP 21.</p>
+ <p>
+ Own Id: OTP-15333 Aux Id: ERL-737 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix the seq_trace token to not be cleared when a process
+ receives messages sent by erts. Some examples of when
+ this could happen is all port BIFs, i.e.
+ <c>open_port</c>, <c>port_command</c> etc etc.</p>
+ <p>
+ Fix so that messages sent by nifs can be traced using
+ normal and <c>seq_trace</c> tracing.</p>
+ <p>
+ Own Id: OTP-15038 Aux Id: ERL-602 </p>
+ </item>
+ <item>
+ <p>
+ Fixed specs and documentation for <c>process_info</c>
+ item <c>monitored_by</c> to include port identifiers and
+ nif resources as possible types.</p>
+ <p>
+ Own Id: OTP-15180 Aux Id: ERL-648 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug in generation of erl_crash.dump, which could
+ cause VM to crash.</p>
+ <p>
+ Bug exist since erts-9.2 (OTP-20.2).</p>
+ <p>
+ Own Id: OTP-15181</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where ctrl-break or ctrl-c would not trigger the
+ break mode properly on Windows. This bug was introduced
+ in erts-10.0 (OTP-21).</p>
+ <p>
+ Own Id: OTP-15205</p>
+ </item>
+ <item>
+ <p>
+ Fix a performance bug for reception of UDP packages,
+ where a memory buffer would be reallocated when it should
+ not have been.</p>
+ <p>
+ Introduce a limit on the maximum automatic increase of
+ the UDP user-space buffer to the theoretical max of the
+ network PATH, i.e. 65535.</p>
+ <p>
+ Own Id: OTP-15206</p>
+ </item>
+ <item>
+ <p>
+ Fix alignment of erts allocator state internally in erts.
+ With the improper alignment the emulator would refuse to
+ start when compiled with clang on 32-bit systems.</p>
+ <p>
+ Own Id: OTP-15208 Aux Id: PR-1897 ERL-677 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug where too many concurrent calls to
+ <c>erlang:open_port({spawn,"cmd"},...)</c> would result
+ in the emulator terminating with the reason "Failed to
+ write to erl_child_setup: ". After this fix the
+ <c>open_port</c> call will throw an <c>emfile</c>
+ exception instead.</p>
+ <p>
+ Own Id: OTP-15210</p>
+ </item>
+ <item>
+ <p>
+ Upgraded the ERTS internal PCRE library from version 8.41
+ to version 8.42. See <url
+ href="http://pcre.org/original/changelog.txt">http://pcre.org/original/changelog.txt</url>
+ for information about changes made to PCRE. This library
+ implements major parts of the <seealso
+ marker="stdlib:re"><c>re</c></seealso> regular
+ expressions module.</p>
+ <p>
+ Own Id: OTP-15217</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>open_port({fd,X,Y}, ...)</c> to release the file
+ descriptors from the pollset when closing the port.
+ Without this fix the same file descriptor number could
+ not be reused when doing multiple open_port and
+ port_close sequences.</p>
+ <p>
+ Own Id: OTP-15236 Aux Id: ERL-692 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>float_to_list/2</c> and
+ <c>float_to_binary/2</c> with options
+ <c>[{decimals,0},compact]</c> causing totally wrong
+ results. Bug exists since OTP-21.0.</p>
+ <p>
+ Own Id: OTP-15276 Aux Id: PR-1920 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:memory</c> causing <c>ets</c> to
+ report too much. This small false memory leak (16 bytes
+ each time) can only happen when a specific race condition
+ occurs between scheduler threads on a table with option
+ <c>write_concurrency</c>.</p>
+ <p>
+ Own Id: OTP-15278</p>
+ </item>
+ <item>
+ <p>
+ Minor <c>configure</c> test fixes</p>
+ <p>
+ Own Id: OTP-15282</p>
+ </item>
+ <item>
+ <p>
+ Improved robustness of distribution connection setup. In
+ OTP-21.0 a truly asynchronous connection setup was
+ introduced. This is further improvement on that work to
+ make the emulator more robust and also be able to recover
+ in cases when involved Erlang processes misbehave.</p>
+ <p>
+ Own Id: OTP-15297 Aux Id: OTP-15279, OTP-15280 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ The socket options <c>recvtos</c>, <c>recvttl</c>,
+ <c>recvtclass</c> and <c>pktoptions</c> have been
+ implemented in the socket modules. See the documentation
+ for the <c>gen_tcp</c>, <c>gen_udp</c> and <c>inet</c>
+ modules. Note that support for these in the runtime
+ system is platform dependent. Especially for
+ <c>pktoptions</c> which is very Linux specific and
+ obsoleted by the RFCs that defined it.</p>
+ <p>
+ Own Id: OTP-15145 Aux Id: ERIERL-187 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.8</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ As of ERTS version 10.0 (OTP 21.0) the
+ <c>erl_child_setup</c> program, which creates port
+ programs, ignores <c>TERM</c> signals. This setting was
+ unintentionally inherited by port programs. Handling of
+ <c>TERM</c> signals in port programs has now been
+ restored to the default behavior. That is, terminate the
+ process.</p>
+ <p>
+ Own Id: OTP-15289 Aux Id: ERIERL-235, OTP-14943, ERL-576 </p>
+ </item>
+ <item>
+ <p>
+ The fix made for OTP-15279 in erts-10.07 (OTP-21.0.8) was
+ not complete. It could cause a new connection attempt to
+ be incorrectly aborted in certain cases. This fix will
+ amend that flaw.</p>
+ <p>
+ Own Id: OTP-15296 Aux Id: OTP-15279, ERIERL-226 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.7</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A process could get stuck in an infinite rescheduling
+ loop between normal and dirty schedulers. This bug was
+ introduced in ERTS version 10.0.</p>
+ <p>
+ Thanks to Maxim Fedorov for finding and fixing this
+ issue.</p>
+ <p>
+ Own Id: OTP-15275 Aux Id: PR-1943 </p>
+ </item>
+ <item>
+ <p>
+ Garbage collection of a distribution entry could cause an
+ emulator crash if <c>net_kernel</c> had not brought
+ previous connection attempts on it down properly.</p>
+ <p>
+ Own Id: OTP-15279 Aux Id: ERIERL-226 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.6</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A race between termination of a process and resume of the
+ same process via <c>erlang:resume_process/1</c> could
+ cause the VM to crash. This bug was introduced in erts
+ version 10.0 (OTP 21.0).</p>
+ <p>
+ Own Id: OTP-15237</p>
+ </item>
+ <item>
+ <p>
+ When tracing on <c>running</c>, <c>in</c> trace events
+ could be lost when a process was rescheduled between a
+ dirty and a normal scheduler.</p>
+ <p>
+ Own Id: OTP-15269 Aux Id: ERL-713 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a bug which caused an emulator crash when
+ <c>enif_send()</c> was called by a NIF that executed on a
+ dirty scheduler. The bug was either triggered when the
+ NIF called <c>enif_send()</c> without a message
+ environment, or when the process executing the NIF was
+ <c>send</c> traced.</p>
+ <p>
+ Own Id: OTP-15223</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug causing some Erlang references to be
+ inconsistently ordered. This could for example cause
+ failure to look up certain elements with references as
+ keys in search data structures. This bug was introduced
+ in R13B02.</p>
+ <p>
+ Thanks to Simon Cornish for finding the bug and supplying
+ a fix.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15225</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a bug that prevented the <c>noshell</c> option
+ from working correctly on Mac OS X and BSD.</p>
+ <p>
+ Own Id: OTP-15169</p>
+ </item>
+ <item>
+ <p>Fixed a crash when matching directly against a literal
+ map using a single key that had been saved on the
+ stack.</p>
+ <p>
+ Own Id: OTP-15184</p>
+ </item>
+ <item>
+ <p>Fix node crash when passing a bad time option to
+ <c>file:read_file_info/2</c>.</p>
+ <p>
+ Own Id: OTP-15196</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a scheduler bug that caused normal schedulers to
+ run dirty code.</p>
+ <p>
+ Own Id: OTP-15154</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug in <c>erlang:trace_info/2</c> which caused
+ the emulator to crash when a bad argument was passed. The
+ bug was introduced in ERTS version 10.0.</p>
+ <p>
+ Own Id: OTP-15183 Aux Id: ERL-670 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a rare bug that could cause processes to be
+ scheduled after they had been freed.</p>
+ <p>
+ Own Id: OTP-15067 Aux Id: ERL-573 </p>
+ </item>
+ <item>
+ <p>Fixed a race condition in the inet driver that could
+ cause receive to hang when the emulator was compiled with
+ gcc 8.</p>
+ <p>
+ Own Id: OTP-15158 Aux Id: ERL-654 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>The keys used in <c>os:getenv</c> and <c>os:putenv</c>
+ are case-insensitive again on Windows.</p>
+ <p>
+ Own Id: OTP-15147 Aux Id: ERL-644 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The type specifications for <c>file:posix/0</c> and
+ <c>inet:posix/0</c> have been updated according to which
+ errors file and socket operations should be able to
+ return.</p>
+ <p>
+ Own Id: OTP-14019 Aux Id: ERL-550 </p>
+ </item>
+ <item>
+ <p>
+ Fix error printout from run_erl and a bug that could
+ cause unintended fds to be leaked into the started
+ program.</p>
+ <p>
+ Own Id: OTP-14537 Aux Id: PR1529 </p>
+ </item>
+ <item>
+ <p> File operations used to accept <seealso
+ marker="kernel:file#type-name_all">filenames</seealso>
+ containing null characters (integer value zero). This
+ caused the name to be truncated and in some cases
+ arguments to primitive operations to be mixed up.
+ Filenames containing null characters inside the filename
+ are now <em>rejected</em> and will cause primitive file
+ operations to fail. </p> <p> Also environment variable
+ operations used to accept <seealso
+ marker="kernel:os#type-env_var_name">names</seealso> and
+ <seealso
+ marker="kernel:os#type-env_var_value">values</seealso> of
+ environment variables containing null characters (integer
+ value zero). This caused operations to silently produce
+ erroneous results. Environment variable names and values
+ containing null characters inside the name or value are
+ now <em>rejected</em> and will cause environment variable
+ operations to fail. </p> <p>Primitive environment
+ variable operations also used to accept the <c>$=</c>
+ character in environment variable names causing various
+ problems. <c>$=</c> characters in environment variable
+ names are now also <em>rejected</em>. </p> <p>Also
+ <seealso
+ marker="kernel:os#cmd/1"><c>os:cmd/1</c></seealso> now
+ reject null characters inside its <seealso
+ marker="kernel:os#type-os_command">command</seealso>.
+ </p> <p><seealso
+ marker="erts:erlang#open_port/2"><c>erlang:open_port/2</c></seealso>
+ will also reject null characters inside the port name
+ from now on.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14543 Aux Id: ERL-370 </p>
+ </item>
+ <item>
+ <p>
+ Fix bugs related to the bookkeeping of microstate
+ accounting states.</p>
+ <p>
+ Own Id: OTP-14652</p>
+ </item>
+ <item>
+ <p><c>os:putenv</c> and <c>os:getenv</c> no longer access
+ the process environment directly and instead work on a
+ thread-safe emulation. The only observable difference is
+ that it's <em>not</em> kept in sync with libc
+ <c>getenv(3)</c> / <c>putenv(3)</c>, so those who relied
+ on that behavior in drivers or NIFs will need to add
+ manual synchronization.</p> <p>On Windows this means that
+ you can no longer resolve DLL dependencies by modifying
+ the <c>PATH</c> just before loading the driver/NIF. To
+ make this less of a problem, the emulator now adds the
+ target DLL's folder to the DLL search path.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14666</p>
+ </item>
+ <item>
+ <p>Corrected <c>erlang:is_builtin(erlang, M, F)</c> to
+ return <c>true</c> for <c>apply/2</c> and
+ <c>yield/0</c>.</p>
+ <p>
+ Own Id: OTP-14713 Aux Id: ERL-500 </p>
+ </item>
+ <item>
+ <p>Fixed a bug where the PATH environment variable wasn't
+ updated correctly on a release downgrade, effectively
+ keeping the PATH of the new release.</p>
+ <p>
+ Own Id: OTP-14719</p>
+ </item>
+ <item>
+ <p>A receive optimization that avoids scanning the entire
+ message queue when receiving a message containing a
+ freshly created reference could in rare circumstances
+ (involving recursive calls to the functions that does the
+ receive) cause the receive to hang. This has been
+ corrected.</p>
+ <p>
+ Own Id: OTP-14782 Aux Id: ERL-511 </p>
+ </item>
+ <item>
+ <p>
+ Fix building of Erlang/OTP on platforms which have small
+ data area with short addressing. For example the
+ PowerPC/RTEMS platform.</p>
+ <p>
+ Own Id: OTP-14909 Aux Id: PR-1692 </p>
+ </item>
+ <item>
+ <p>Fixed a crash when <c>enif_make_binary</c> is called
+ with a binary produced by <c>enif_inspect_binary</c> in a
+ different environment.</p>
+ <p>
+ Own Id: OTP-14931</p>
+ </item>
+ <item>
+ <p>Fixed a crash when <c>enif_make_binary</c> is called
+ more than once with a binary that had previously been
+ added to an <c>enif_ioq</c>.</p>
+ <p>
+ Own Id: OTP-14932</p>
+ </item>
+ <item>
+ <p>
+ The erl_child_setup program now ignores SIGTERM signals.</p>
+ <p>
+ Own Id: OTP-14943 Aux Id: ERL-576 </p>
+ </item>
+ <item>
+ <p>
+ Force 64-bit alignment on pre-allocators on architectures
+ which needs it.</p>
+ <p>
+ Own Id: OTP-14977</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug where dirty scheduler picked up non-dirty
+ work.</p>
+ <p>
+ Own Id: OTP-14978</p>
+ </item>
+ <item>
+ <p>
+ Calls to <c>gen_tcp:send/2</c> on closed sockets now
+ returns <c>{error, closed}</c> instead of
+ <c>{error,enotconn}</c>.</p>
+ <p>
+ Own Id: OTP-15001</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:monotonic_time/1</c> failed with <c>badarg</c>
+ when passing the <c>perf_counter</c> time unit as
+ argument.</p>
+ <p>
+ Own Id: OTP-15008</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where rapid <c>init:restart()</c> calls would
+ sometimes crash because a code load request leaked in
+ between the restarts.</p>
+ <p>
+ Own Id: OTP-15013</p>
+ </item>
+ <item>
+ <p>
+ Improve <c>float_to_list(F, [{decimals,D}])</c> to closer
+ conform with <c>io_lib:format("~.*f", [D,F])</c>.</p>
+ <p>
+ There are however, still cases when <c>float_to_list</c>
+ does not produce the exact same result as
+ <c>io_lib:format</c>, especially for large values
+ <c>F</c> and/or many decimals <c>D</c>.</p>
+ <p>
+ Own Id: OTP-15015 Aux Id: OTP-14890 </p>
+ </item>
+ <item>
+ <p>Fixed a deadlock that would occur on certain
+ allocators when a reallocation failed with <c>+ramv</c>
+ enabled.</p>
+ <p>
+ Own Id: OTP-15024</p>
+ </item>
+ <item>
+ <p>
+ Fix bug that made it impossible to use an erl_tracer as
+ the seq_trace trace receiver.</p>
+ <p>
+ Own Id: OTP-15029</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where a large (> 1 GB) emulator generated error
+ logger message would cause the emulator to crash.</p>
+ <p>
+ Own Id: OTP-15032</p>
+ </item>
+ <item>
+ <p>The emulator will no longer crash when reading the
+ file information of an ordinary file that has an NTFS
+ reparse point, such as files stored in a OneDrive-mapped
+ folder.</p>
+ <p>
+ Own Id: OTP-15062 Aux Id: ERL-615 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>enif_binary_to_term</c> which could cause
+ memory corruption for immediate terms (atoms, small
+ integers, pids, ports, empty lists).</p>
+ <p>
+ Own Id: OTP-15080</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:system_profile/2</c> that could
+ cause superfluous <c>{profile,_,active,_,_}</c> messages
+ for terminating processes.</p>
+ <p>
+ Own Id: OTP-15085</p>
+ </item>
+ <item>
+ <p>
+ On OSs with per thread CPU time support, change
+ <c>cpu_timestamp</c> in <seealso
+ marker="erlang#trace/3">erlang:trace/3</seealso> to use
+ it instead of per process CPU time. This makes this
+ option useable on such OSs when running multiple
+ schedulers.</p>
+ <p>
+ Own Id: OTP-15090</p>
+ </item>
+ <item>
+ <p>
+ Fix segfault in abort_signal_task which could happen if a
+ port terminated while there were outstanding port tasks
+ that were not signals, for example a
+ ready_input/ready_output event.</p>
+ <p>
+ Own Id: OTP-15108 Aux Id: ERL-621 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>ets</c> that could cause VM crash if
+ process A terminates after fixating a table and process B
+ deletes the table at "the same time". The table fixation
+ could be done with <c>ets:safe_fixtable</c> or if process
+ A terminates in the middle of a long running
+ <c>select</c> or <c>match</c> call.</p>
+ <p>
+ Own Id: OTP-15109</p>
+ </item>
+ <item>
+ <p>Owner and group changes through
+ <c>file:write_file_info</c>, <c>file:change_owner</c>,
+ and <c>file:change_group</c> will no longer report
+ success on permission errors.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15118</p>
+ </item>
+ <item>
+ <p>
+ Fix a bug error reporting from escripts on windows where
+ the error message would get garbled.</p>
+ <p>
+ Own Id: OTP-15119 Aux Id: PR-1826 </p>
+ </item>
+ <item>
+ <p>
+ Fix segfault when a process is interally re-scheduled
+ while being traced for in out events. This bug was
+ introduced in erts-8.0 (OTP-19.0).</p>
+ <p>
+ Own Id: OTP-15125</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>It is now possible to open device files and FIFOs with
+ <c>file:open/2</c>.</p>
+ <p>
+ Own Id: OTP-11462</p>
+ </item>
+ <item>
+ <p>
+ The <c>erlang:system_flag(scheduler_wall_time,Bool)</c>
+ call is now reference counted and will be turned off if
+ the (last) process that started the performance
+ statistics dies. Thus it is no longer possible to start
+ the statistics with <c>rpc:call(Node, erlang,
+ system_flag, [scheduler_wall_time, true])</c> since it
+ will be turned off directly afterwards when the rpc
+ process dies.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11694</p>
+ </item>
+ <item>
+ <p>A new logging API is added to Erlang/OTP, see the
+ <seealso
+ marker="kernel:logger"><c>logger(3)</c></seealso> manual
+ page, and section <seealso
+ marker="kernel:logger_chapter">Logging</seealso> in the
+ Kernel User's Guide.</p>
+ <p>Calls to <c>error_logger</c> are automatically
+ redirected to the new API, and legacy error logger event
+ handlers can still be used. It is, however, recommended
+ to use the Logger API directly when writing new code.</p>
+ <p>Notice the following potential incompatibilities:</p>
+ <list> <item><p>Kernel configuration parameters
+ <c>error_logger</c> still works, but is overruled if the
+ default handler's output destination is configured with
+ Kernel configuration parameter <c>logger</c>.</p> <p>In
+ general, parameters for configuring error logger are
+ overwritten by new parameters for configuring
+ Logger.</p></item> <item><p>The concept of SASL error
+ logging is deprecated, meaning that by default the SASL
+ application does not affect which log events are
+ logged.</p> <p>By default, supervisor reports and crash
+ reports are logged by the default Logger handler started
+ by Kernel, and end up at the same destination (terminal
+ or file) as other standard log event from Erlang/OTP.</p>
+ <p>Progress reports are not logged by default, but can be
+ enabled by setting the primary log level to info, for
+ example with the Kernel configuration parameter
+ <c>logger_level</c>.</p> <p>To obtain backwards
+ compatibility with the SASL error logging functionality
+ from earlier releases, set Kernel configuration parameter
+ <c>logger_sasl_compatible</c> to <c>true</c>. This
+ prevents the default Logger handler from logging any
+ supervisor-, crash-, or progress reports. Instead, SASL
+ adds a separate Logger handler during application start,
+ which takes care of these log events. The SASL
+ configuration parameters <c>sasl_error_logger</c> and
+ <c>sasl_errlog_type</c> specify the destination (terminal
+ or file) and severity level to log for these
+ events.</p></item></list>
+ <p>
+ Since Logger is new in Erlang/OTP 21.0, we do reserve the
+ right to introduce changes to the Logger API and
+ functionality in patches following this release. These
+ changes might or might not be backwards compatible with
+ the initial version.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13295</p>
+ </item>
+ <item>
+ <p>
+ <c>gen_sctp:connect_init/4</c> or rather connect in
+ <c>inet_drv.c</c> for SCTP has been fixed to not check
+ the write file descriptor for writeability after a
+ connect, since for SCTP (SOCK_SEQPACKET) that property
+ does not seem to be any kind of indicator for when a
+ connect has finished. This fixes connects that the OS
+ returned as "in progress" that was misinterpreted by
+ <c>gen_sctp:connect_init</c> as failed.</p>
+ <p>
+ Own Id: OTP-13760 Aux Id: PR-1592 </p>
+ </item>
+ <item>
+ <p>The file driver has been rewritten as a NIF,
+ decreasing the latency of file operations. Notable
+ incompatibilities are:</p> <list> <item><p>The
+ <c>use_threads</c> option for <c>file:sendfile/5</c> no
+ longer has any effect; we either use non-blocking
+ <c>sendfile(2)</c> or fall back to <c>file:read</c> +
+ <c>gen_tcp:send</c>. </p></item> <item><p>The
+ file-specific DTrace probes have been removed. The same
+ effect can be achieved with normal tracing together with
+ the <c>nif__entry</c>/<c>nif__return</c> probes to track
+ scheduling.</p></item> </list>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14256</p>
+ </item>
+ <item>
+ <p>The I/O polling functionality of erts has been
+ re-written to better make use of the OSs polling
+ mechanisms. This change means that erts will now always
+ prefer to use a kernel-polling mechanism if possible.
+ Also all of the I/O polling has been moved to dedicated
+ threads instead of being placed in the scheduler
+ loops.</p> <p>As a result of this, the <c>erl</c> options
+ <c>+K</c> and <c>+secio</c> have been removed. It is
+ still possible to disable kernel-poll, but it has to be
+ done at compile time through the configure option
+ <c>--disable-kernel-poll</c>.</p> <p>The new <c>erl</c>
+ options <seealso marker="erl#+IOt"><c>+IOt</c></seealso>
+ and <seealso marker="erl#+IOp"><c>+IOp</c></seealso> can
+ be used to change how many IO poll threads and poll sets
+ that erts should use. See their respective documentation
+ for more details.</p>
+ <p>
+ Own Id: OTP-14346</p>
+ </item>
+ <item>
+ <p>Truly asynchronous auto-connect. Earlier, when
+ <c>erlang:send</c> was aimed toward an unconnected node,
+ the function would not return until the connection setup
+ had completed (or failed). Now the function returns
+ directly after the message has been enqueued and the
+ connection setup started.</p>
+ <p>The same applies to all distributed operations that
+ may trigger auto-connect, i.e. <c>'!'</c>, <c>send</c>,
+ <c>link</c>, <c>monitor</c>, <c>monitor_node</c>,
+ <c>exit/2</c> and <c>group_leader</c>.</p>
+ <p>The interface for all these functions are unchanged as
+ they do not return connection failures. The only
+ exception is <c>erlang:monitor</c> where a <em>possible
+ incompatibility</em> is introduced: An attempt to monitor
+ a process on a primitive node (such as erl_interface or
+ jinterface), where remote process monitoring is not
+ implemented, will no longer fail with <c>badarg</c>
+ exception. Instead a monitor will be created, but it will
+ only supervise the connection to the node.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14370</p>
+ </item>
+ <item>
+ <p>Changed the default behaviour of <c>.erlang</c>
+ loading: <c>.erlang</c> is no longer loaded from the
+ current directory. <c>c:erlangrc(PathList)</c> can be
+ used to search and load an <c>.erlang</c> file from user
+ specified directories.</p> <p><c>escript</c>,
+ <c>erlc</c>, <c>dialyzer</c> and <c>typer</c> no longer
+ load an <c>.erlang</c> at all.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14439</p>
+ </item>
+ <item>
+ <p>
+ New functionality for implementation of alternative
+ carriers for the Erlang distribution has been introduced.
+ This mainly consists of support for usage of distribution
+ controller processes (previously only ports could be used
+ as distribution controllers). For more information see
+ <seealso marker="erts:alt_dist#distribution_module">ERTS
+ User's Guide ➜ How to implement an Alternative Carrier
+ for the Erlang Distribution ➜ Distribution
+ Module</seealso>.</p>
+ <p>
+ Own Id: OTP-14459</p>
+ </item>
+ <item>
+ <p>
+ Add support for the lcc compiler and in extension the
+ Elbrus 2000 platform.</p>
+ <p>
+ Own Id: OTP-14492</p>
+ </item>
+ <item>
+ <p>Support for "tuple calls" have been removed from the
+ run-time system. Tuple calls was an undocumented and
+ unsupported feature which allowed the module argument for
+ an apply operation to be a tuple: <c>Var = dict:new(),
+ Var:size()</c>. This "feature" frequently caused
+ confusion, especially when such call failed. The
+ stacktrace would point out functions that don't exist in
+ the source code.</p>
+ <p>For legacy code that need to use parameterized modules
+ or tuple calls for some other reason, there is a new
+ compiler option called <c>tuple_calls</c>. When this
+ option is given, the compiler will generate extra code
+ that emulates the old behavior for calls where the module
+ is a variable.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14497</p>
+ </item>
+ <item>
+ <p>Creation of small maps with literal keys has been
+ optimized to be faster and potentially use less memory.
+ The keys are combined into a literal key tuple which is
+ put into the literal pool. The key tuple can be shared
+ between many instances of maps having the same keys.</p>
+ <p>
+ Own Id: OTP-14502</p>
+ </item>
+ <item>
+ <p>
+ When an exception is thrown, include the arguments of the
+ call in the stacktrace for BIFs <c>band</c>, <c>bor</c>,
+ <c>bsl</c>, <c>bsr</c>, <c>bxor</c>, <c>div</c>,
+ <c>rem</c> and the operators <c>+</c>, <c>-</c>, <c>*</c>
+ and <c>/</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14508</p>
+ </item>
+ <item>
+ <p>
+ The non-smp emulators have been removed. This means that
+ the configure options <c>--disable-threads</c> and
+ <c>--enable-plain-emulator</c> have been removed and
+ configure will now refuse to build Erlang/OTP on
+ platforms without thread support.</p>
+ <p>
+ In order to achieve a similar setup as the non-smp
+ emulator, it is possible to start Erlang/OTP with the
+ <c>+S 1</c> option.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14518</p>
+ </item>
+ <item>
+ <p>Modules that use floating point constants compiled
+ with R15 or earlier will need to be re-compiled before
+ they can be loaded.</p>
+ <p>
+ Own Id: OTP-14575</p>
+ </item>
+ <item>
+ <p>
+ Implementation of true asynchronous signaling between
+ processes in order to improve scalability. Signals
+ affected include exit, monitor, demonitor, monitor
+ triggered, link, unlink, and group leader.</p>
+ <p>
+ Own Id: OTP-14589</p>
+ </item>
+ <item>
+ <p>
+ Added a PGO (profile guided optimization) pass to the
+ build step of erts. This can be disabled by passing
+ --disable-pgo to configure.</p>
+ <p>
+ Own Id: OTP-14604</p>
+ </item>
+ <item>
+ <p>
+ Improved the performance of <c>binary:split</c> and
+ <c>binary:match</c>.</p>
+ <p>
+ Own Id: OTP-14610 Aux Id: PR-1480 </p>
+ </item>
+ <item>
+ <p>
+ It is not longer possible to disable dirty schedulers
+ when building erlang.</p>
+ <p>
+ Own Id: OTP-14613</p>
+ </item>
+ <item>
+ <p>Loaded BEAM code in a 64-bit system requires less
+ memory because of better packing of operands for
+ instructions.</p>
+ <p>These memory savings were achieved by major
+ improvements to the <c>beam_makeops</c> scripts used when
+ building the run time system and BEAM compiler. There is
+ also new for documentation for <c>beam_makeops</c> that
+ describes how new BEAM instructions and loader
+ transformations can be implemented. The documentation is
+ found in here in a source directory or git repository:
+ erts/emulator/internal_doc/beam_makeops.md. An online
+ version can be found here:
+ https://github.com/erlang/otp/blob/master/erts/emulator/internal_doc/beam_makeops.md</p>
+ <p>
+ Own Id: OTP-14626</p>
+ </item>
+ <item>
+ <p><c>file:read_file</c> has been changed to read the
+ content of files that report a size of 0 even when data
+ can be read from them. An example of such a file is
+ <c>/proc/cpuinfo</c> on Linux.</p>
+ <p>
+ Own Id: OTP-14637 Aux Id: ERL-327 PR-1524 </p>
+ </item>
+ <item>
+ <p>
+ It is no longer possible to disable the <c>temp_alloc</c>
+ allocator. Disabling it caused serious performance
+ degradations and was never what was wanted.</p>
+ <p>
+ Own Id: OTP-14651</p>
+ </item>
+ <item>
+ <p>The reduction cost of sending messages is now
+ constant. It will no longer scale according to the length
+ of the receiving process' message queue.</p>
+ <p>
+ Own Id: OTP-14667</p>
+ </item>
+ <item>
+ <p>
+ Improved loading of modules with <c>-on_load</c>
+ directive, to no longer block all schedulers when the
+ load operation is completed.</p>
+ <p>
+ Own Id: OTP-14680</p>
+ </item>
+ <item>
+ <p>
+ On platforms with real-time signals available, SIGRTMIN+1
+ is now used as the internal scheduler suspend signal
+ instead of SIGUSR2.</p>
+ <p>
+ Own Id: OTP-14682</p>
+ </item>
+ <item>
+ <p>When the value returned from a '<c>catch</c>'
+ expression is ignored, no stacktrace will be built if an
+ exception is caught. That will save time and produce less
+ garbage. There are also some minor optimizations of
+ '<c>try</c>/<c>catch</c>' both in the compiler and
+ run-time system.</p>
+ <p>
+ Own Id: OTP-14683</p>
+ </item>
+ <item>
+ <p>The guarantees and non-guarantees of
+ <c>erlang:get_stacktrace/0</c> are now documented.</p>
+ <p>
+ Own Id: OTP-14687</p>
+ </item>
+ <item>
+ <p>There is a new syntax in '<c>try/catch</c>' for
+ retrieving the stacktrace without calling
+ '<c>erlang:get_stacktrace/0</c>'. See the reference
+ manual for a description of the new syntax. The
+ '<c>erlang:get_stacktrace/0</c>' BIF is now
+ deprecated.</p>
+ <p>
+ Own Id: OTP-14692</p>
+ </item>
+ <item>
+ <p>
+ New 'used' option for <c>binary_to_term/2</c> that will
+ also return number of bytes actually read from the
+ binary. This enables easy access to any extra data in the
+ binary located directly after the returned term.</p>
+ <p>
+ Own Id: OTP-14780</p>
+ </item>
+ <item>
+ <p>
+ Added more statistics for
+ <c>erlang:system_info({allocator,A})</c> in the
+ <c>mbcs_pool</c> section.</p>
+ <p>
+ Own Id: OTP-14795 Aux Id: ERL-88 </p>
+ </item>
+ <item>
+ <p>Added <c>enif_ioq_peek_head</c> to retrieve Erlang
+ terms from NIF IO queues without having to resort to
+ copying.</p>
+ <p>
+ Own Id: OTP-14797</p>
+ </item>
+ <item>
+ <p>There is a new option '<c>makedep_side_effect</c>' for
+ the compiler and <c>-MMD</c> for '<c>erlc</c>' that
+ generates dependencies and continues to compile as
+ normal.</p>
+ <p>
+ Own Id: OTP-14830</p>
+ </item>
+ <item>
+ <p>Added <c>ets:whereis/1</c> for retrieving the table
+ identifier of a named table.</p>
+ <p>
+ Own Id: OTP-14884</p>
+ </item>
+ <item>
+ <p><c>seq_trace</c> labels may now be any erlang
+ term.</p>
+ <p>
+ Own Id: OTP-14899</p>
+ </item>
+ <item>
+ <p>
+ Optimized the common case of <c>monitor</c> followed by
+ <c>send</c> to the same local process. The monitor signal
+ is now delayed in order to be piggybacked with the sent
+ message and thereby only get one lock operation on the
+ message queue of the receiver. A delayed monitor signal
+ is flushed if no <c>send</c> has been done at the latest
+ when the process is scheduled out.</p>
+ <p>
+ Own Id: OTP-14901</p>
+ </item>
+ <item>
+ <p>
+ Make hipe compiled code work on x86_64 (amd64) with OS
+ security feature PIE, where executable code can be loaded
+ into a random location. Old behavior, if hipe was
+ enabled, was to disable PIE build options for the VM.</p>
+ <p>
+ Own Id: OTP-14903</p>
+ </item>
+ <item>
+ <p>The number of driver async threads will now default to
+ 1 as the standard drivers do not use them anymore. Users
+ that changed this value to tweak the file driver should
+ replace <c>+A</c> with <c>+SDio</c> since it now uses
+ dirty IO schedulers instead of async threads.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14928</p>
+ </item>
+ <item>
+ <p>
+ Optimize <c>==</c> and <c>/=</c> for binaries with
+ different sizes to be constant in time instead of
+ proportional to the size of their common prefix.</p>
+ <p>
+ Own Id: OTP-14934 Aux Id: PR-1708 </p>
+ </item>
+ <item>
+ <p>
+ Refactorings making some internal process flags available
+ for other usage.</p>
+ <p>
+ Own Id: OTP-14948</p>
+ </item>
+ <item>
+ <p>
+ Removed need for HiPE to allocate native executable
+ memory in low 2GB address space on x86_64. Command line
+ option <c>+MXscs</c> is thereby obsolete and ignored.</p>
+ <p>
+ Own Id: OTP-14951</p>
+ </item>
+ <item>
+ <p>Added <c>enif_make_map_from_arrays</c> for creating a
+ populated map, analogous to
+ <c>enif_make_list_from_array</c>.</p>
+ <p>
+ Own Id: OTP-14954</p>
+ </item>
+ <item>
+ <p>Added configuration switches for busy-wait and wake up
+ thresholds for dirty schedulers, and changing these
+ settings for normal schedulers will no longer affect
+ dirty schedulers. </p> <p>Refer to the documentation for
+ details. The new switches are <seealso
+ marker="erl#+sbwtdcpu">+sbwtdcpu</seealso>, <seealso
+ marker="erl#+sbwtdio">+sbwtdio</seealso>, <seealso
+ marker="erl#+swtdcpu">+swtdcpu</seealso>, and <seealso
+ marker="erl#+swtdio">+swtdio</seealso>.</p> <p>The
+ default busy wait threshold for dirty scheduler threads
+ has also been lowered to <c>short</c>.</p>
+ <p>
+ Own Id: OTP-14959</p>
+ </item>
+ <item>
+ <p>
+ The list of "taints" now also includes dynamic loaded
+ drivers in addition to NIF libraries. Statically linked
+ drivers and NIF libraries that are part of erts are not
+ included. The "taints" are returned by
+ <c>system_info(taints)</c> and printed in the header of
+ <c>erl_crash.dump</c> files.</p>
+ <p>
+ Own Id: OTP-14960</p>
+ </item>
+ <item>
+ <p>Added <c>instrument:allocations</c> and
+ <c>instrument:carriers</c> for retrieving information
+ about memory utilization and fragmentation.</p>
+ <p>The old <c>instrument</c> interface has been removed,
+ as have the related options <c>+Mim</c> and
+ <c>+Mis</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14961</p>
+ </item>
+ <item>
+ <p>The process suspend functionality used by the <seealso
+ marker="erlang#suspend_process/2">erlang:suspend_process/2</seealso>
+ BIF has been reimplemented using the newly introduced
+ true asynchronous signaling between processes. This
+ mainly to reduce memory usage in the process control
+ block of all processes, but also in order to simplify the
+ implementation.</p> <warning> <p>You can easily create
+ deadlocks if processes suspends each other (directly or
+ in circles). In ERTS versions prior to ERTS version 10.0,
+ the runtime system prevented such deadlocks, but this
+ prevention has now been removed due to performance
+ reasons.</p> </warning> <p>Other ERTS internal
+ functionality that used the previous process suspend
+ functionality have also been reimplemented to use
+ asynchronous signaling instead.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14964 Aux Id: OTP-14589 </p>
+ </item>
+ <item>
+ <p>Added the <c>nifs</c> option to
+ <c>?MODULE:module_info/1</c> for listing a module's
+ installed NIF functions.</p>
+ <p>
+ Own Id: OTP-14965</p>
+ </item>
+ <item>
+ <p>
+ New implementation of <c>erlang:process_info/[1,2]</c>.</p>
+ <p>
+ In the general case when inspecting another process, the
+ new implementation sends an asynchronous process-info
+ request signal to the other process and waits for the
+ result instead of locking the other process and reading
+ the result directly. In some special cases where no
+ conflicts occur, signal order wont be violated, and the
+ amount of data requested is guaranteed to be small, the
+ inspected process may be inspected directly.</p>
+ <p>
+ Appropriate amount of reductions are now also bumped when
+ inspecting a process.</p>
+ <p>
+ Own Id: OTP-14966</p>
+ </item>
+ <item>
+ <p>
+ Removed process start time from crash dump in order to
+ save memory in process control block.</p>
+ <p>
+ Own Id: OTP-14975 Aux Id: PR-1597 </p>
+ </item>
+ <item>
+ <p>
+ Optimize <c>erlang:put/2</c> when updating existing key
+ with a new immediate value (atom, small integer, pid,
+ port).</p>
+ <p>
+ Own Id: OTP-14976</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:process_info/1</c> has been changed to no
+ longer include <c>messages</c> by default. Instead
+ <c>erlang:process_info/2</c> should be used.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14986 Aux Id: PR-1745 </p>
+ </item>
+ <item>
+ <p>
+ New <c>erlang:system_info(ets_count)</c> to get total
+ number of ets tables existing at the local node.</p>
+ <p>
+ Own Id: OTP-14987</p>
+ </item>
+ <item>
+ <p>
+ New NIF functions: <c>enif_mutex_name</c>,
+ <c>enif_cond_name</c>, <c>enif_rwlock_name</c>,
+ <c>enif_thread_name</c>, <c>enif_vfprintf</c>,
+ <c>enif_vsnprintf</c>.</p>
+ <p>
+ Own Id: OTP-14994</p>
+ </item>
+ <item>
+ <p>When <c>erlang:system_flag(backtrace_depth, 0)</c> has
+ been called, all exceptions will now contain the entry
+ for <em>one</em> function (despite the zero). It used to
+ be that a hand-made stack backtrace passed to
+ <c>erlang:raise/3</c> would be be truncated to an empty
+ list.</p>
+ <p>
+ Own Id: OTP-15026</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug for named <c>ets</c> tables which could cause
+ unexpected results from matchspec iteration functions
+ (<c>ets:select*</c> and <c>ets:match*</c>) if the table
+ was deleted and recreated with the same name during the
+ iteration. The iteration could incorrectly continue
+ through the recreated table. The expected correct
+ behavior is now for the iteration call to fail with a
+ <c>badarg</c> exception if the table is deleted before
+ the iteration has completed.</p>
+ <p>
+ Own Id: OTP-15031</p>
+ </item>
+ <item>
+ <p>Two new guards BIFs operating on maps have been added:
+ <c>map_get/2</c> and <c>is_map_key/2</c>. They do the
+ same as <c>maps:get/2</c> and <c>maps:is_key/2</c>,
+ respectively, except that they are allowed to be used in
+ guards.</p>
+ <p>
+ Own Id: OTP-15037 Aux Id: PR-1784, PR-1802 </p>
+ </item>
+ <item>
+ <p>
+ Release run-queue lock while cleaning up terminated dirty
+ process.</p>
+ <p>
+ Own Id: OTP-15081</p>
+ </item>
+ <item>
+ <p>The callback module passed as <c>-epmd_module</c> to
+ erl has been expanded to be able to do name and port
+ resolving.</p> <p>Documentation has also been added in
+ the <seealso
+ marker="kernel:erl_epmd"><c>erl_epmd</c></seealso>
+ reference manual and ERTS User's Guide <seealso
+ marker="erts:alt_disco">How to Implement an Alternative
+ Service Discovery for Erlang Distribution</seealso>.</p>
+ <p>
+ Own Id: OTP-15086 Aux Id: PR-1694 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Erts 9.3.3.9</title>
<section><title>Improvements and New Features</title>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-29 05:06:07 +0000