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diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml index 4924f63e38..8336c1e3d6 100644 --- a/erts/doc/src/notes.xml +++ 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<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> |