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Diffstat (limited to 'erts/doc/src/notes.xml')
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1 files changed, 2285 insertions, 33 deletions
diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml index eba4cdf06f..f816cdf3a8 100644 --- a/erts/doc/src/notes.xml +++ b/erts/doc/src/notes.xml @@ -4,20 +4,21 @@ <chapter> <header> <copyright> - <year>2004</year><year>2013</year> + <year>2004</year><year>2015</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -30,6 +31,2230 @@ </header> <p>This document describes the changes made to the ERTS application.</p> + +<section><title>Erts 7.3.1.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed a race that could cause a lost wakeup of a process + that timed out in a <c>receive ... after</c>. This bug + was introduced in ERTS version 7.0.</p> + <p> + Own Id: OTP-13798 Aux Id: OTP-11997 </p> + </item> + <item> + <p> + Fixed segfault after writing an erl crash dump.</p> + <p> + Own Id: OTP-13799</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.3.1.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix scheduler deadlock bug in <c>ets:update_counter/4</c> + when key is not found and inserting the default object + causes the table to grow.</p> + <p> + Own Id: OTP-13731 Aux Id: ERL-188 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.3.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + <c>process_info(Pid, last_calls)</c> did not work for + <c>Pid /= self()</c>.</p> + <p> + Own Id: OTP-13418</p> + </item> + <item> + <p> + Make sure to create a crash dump when running out of + memory. This was accidentally removed in the erts-7.3 + release.</p> + <p> + Own Id: OTP-13419</p> + </item> + <item> + <p> + Schedulers could be woken by a premature timeout on + Linux. This premature wakeup was however harmless.</p> + <p> + Own Id: OTP-13420</p> + </item> + <item> + <p> + A process communicating with a port via one of the + <c>erlang:port_*</c> BIFs could potentially end up in an + inconsistent state if the port terminated during the + communication. When this occurred the process could later + block in a <c>receive</c> even though it had messages + matching in its message queue.</p> + <p> + This bug was introduced in erts version 5.10 (OTP R16A).</p> + <p> + Own Id: OTP-13424 Aux Id: OTP-10336 </p> + </item> + <item> + <p> + The reference count of a process structure could under + rare circumstances be erroneously managed. When this + happened invalid memory accesses occurred.</p> + <p> + Own Id: OTP-13446</p> + </item> + <item> + <p> + Fix race between <c>process_flag(trap_exit,true)</c> and + a received exit signal.</p> + <p> + A process could terminate due to exit signal even though + <c>process_flag(trap_exit,true)</c> had returned. A very + specific timing between call to <c>process_flag/2</c> and + exit signal from another scheduler was required for this + to happen.</p> + <p> + Own Id: OTP-13452</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The '-path' flag to 'erl' has been documented. This flag + replaces the path specified in the boot script. It has + always existed, but was earlier only documented in SASL + (script).</p> + <p> + Own Id: OTP-13060</p> + </item> + <item> + <p> + The <c>call_time</c> tracing functionality internally + used a time based on OS system time in order to measure + call time which could cause erroneous results if OS + system time was changed during tracing.</p> + <p> + This functionality now use Erlang monotonic time in order + to measure time. Besides fixing the erroneous results due + to OS system time being used, the results are often also + better since Erlang monotonic time often has better + accuracy and precision.</p> + <p> + Own Id: OTP-13216</p> + </item> + <item> + <p> + Fix behaviour of -delay_write command line switch of + epmd, which is used for debugging - in some cases epmd + was sleeping twice the requested amount of time.</p> + <p> + Own Id: OTP-13220</p> + </item> + <item> + <p> + Fix race between timeout and exit signal that could cause + a process to ignore the exit signal and continue + execution. Bug exist since OTP 18.0.</p> + <p> + Own Id: OTP-13245</p> + </item> + <item> + <p> + Fix bug in <c>erlang:halt/1,2</c> for large exit status + values, causing either <c>badarg</c> (on 32-bit) or exit + with a crash dump and/or core dump (on 64-bit). Make + <c>erlang:halt/1,2</c> tolerate any non negative integer + as exit status and truncate high order bits if the OS + does not support it.</p> + <p> + Own Id: OTP-13251 Aux Id: ERL-49 </p> + </item> + <item> + <p> + <seealso + marker="kernel:gen_tcp#accept/2"><c>gen_tcp:accept/2</c></seealso> + was not <seealso + marker="erts:time_correction#Time_Warp_Safe_Code">time + warp safe</seealso>. This since it used the same time as + returned by <seealso + marker="erts:erlang#now/0"><c>erlang:now/0</c></seealso> + when calculating timeout. This has now been fixed.</p> + <p> + Own Id: OTP-13254 Aux Id: OTP-11997, OTP-13222 </p> + </item> + <item> + <p> + Fix faulty error handling when writing to a compressed + file.</p> + <p> + Own Id: OTP-13270</p> + </item> + <item> + <p> + Fix sendfile usage for large files on FreeBSD</p> + <p> + Own Id: OTP-13271</p> + </item> + <item> + <p> + Fix bug that could cause + <c>process_info(P,current_location)</c> to crash emulator + for hipe compiled modules.</p> + <p> + Own Id: OTP-13282 Aux Id: ERL-79 </p> + </item> + <item> + <p> + Out of memory errors have been changed to cause an exit + instead of abort.</p> + <p> + Own Id: OTP-13292</p> + </item> + <item> + <p> + When calling <c>garbage_collect/[1,2]</c> or + <c>check_process_code/[2,3]</c> from a process with a + higher priority than the priority of the process operated + on, the run queues could end up in an inconsistent state. + This bug has now been fixed.</p> + <p> + Own Id: OTP-13298 Aux Id: OTP-11388 </p> + </item> + <item> + <p> + A workaround for an issue with older gcc versions (less + than 5) and inline assembly on 32-bit x86 caused an + emulator crash when it had been compiled with a newer gcc + version. An improved <c>configure</c> test, run when + building OTP, now detects whether the workaround should + be used or not.</p> + <p> + Own Id: OTP-13326 Aux Id: ERL-80 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p>Introduced new statistics functionality in order to + more efficiently retrieve information about run able and + active processes and ports. For more information see:</p> + <list> <item><seealso + marker="erlang#statistics_total_run_queue_lengths"><c>statistics(total_run_queue_lengths)</c></seealso></item> + <item><seealso + marker="erlang#statistics_run_queue_lengths"><c>statistics(run_queue_lengths)</c></seealso></item> + <item><seealso + marker="erlang#statistics_total_active_tasks"><c>statistics(total_active_tasks)</c></seealso></item> + <item><seealso + marker="erlang#statistics_active_tasks"><c>statistics(active_tasks)</c></seealso></item> + </list> + <p> + Own Id: OTP-13201</p> + </item> + <item> + <p> + Time warp safety improvements.</p> + <p> + Introduced the options <c>monotonic_timestamp</c>, and + <c>strict_monotonic_timestamp</c> to the trace, + sequential trace, and system profile functionality. This + since the already existing <c>timestamp</c> option is not + time warp safe.</p> + <p> + Introduced the option <c>safe_fixed_monotonic_time</c> to + <c>ets:info/2</c> and <c>dets:info/2</c>. This since the + already existing <c>safe_fixed</c> option is not time + warp safe.</p> + <p> + Own Id: OTP-13222 Aux Id: OTP-11997 </p> + </item> + <item> + <p> + Fix a register race where down nodes goes undetected in + epmd</p> + <p> + Own Id: OTP-13301</p> + </item> + <item> + <p> + Improved the gcc inline assembly implementing double word + atomic compare and exchange on x86/x86_64 so that it also + can be used when compiling with clang.</p> + <p> + Own Id: OTP-13336</p> + </item> + <item> + <p> + An optimization preventing a long wait for a scheduler + thread looking up information about a process executing + on another scheduler thread had unintentionally been lost + in erts-5.10 (OTP R16A). This optimization has now been + reintroduced.</p> + <p> + Own Id: OTP-13365 Aux Id: OTP-9892 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Revert "Fix erroneous splitting of emulator path"</p> + <p> + Own Id: OTP-13202</p> + </item> + <item> + <p> + Fix HiPE enabled emulator for FreeBSD.</p> + <p> + Own Id: OTP-13204 Aux Id: pr926 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Small documentation fixes</p> + <p> + Own Id: OTP-13017</p> + </item> + <item> + <p> + Fix memory corruption bug caused by disabling + distribution and then re-enable distribution with a node + name that has previously been used by a remote node.</p> + <p> + Own Id: OTP-13076 Aux Id: seq12959 </p> + </item> + <item> + <p> + Renamed variables with name bool as Visual Studio 2015 + now treats this is a keyword.</p> + <p> + Own Id: OTP-13079</p> + </item> + <item> + <p><c>erl_prim_loader</c> has not supported custom + loaders for several releases. In the documentation for + <c>erl_prim_loader</c>, all references to custom loaders + have now been removed.</p> + <p> + Own Id: OTP-13102</p> + </item> + <item> + <p> + Fixed compilation of erts together with libc versions + that do not define __uint32_t.</p> + <p> + Own Id: OTP-13105</p> + </item> + <item> + <p> + erl -make now returns non-zero exit codes on failure</p> + <p> + Own Id: OTP-13107</p> + </item> + <item> + <p> + Fix crash on init:restart in embedded mode caused by + on_load handler process not being relaunched leading to + load failure for modules such as crypto and asn1rt_nif + that need it to be present for correct NIF loading.</p> + <p> + Own Id: OTP-13115</p> + </item> + <item> + <p> + Fix maps decode in erlang:binary_to_term/1</p> + <p>Decoding a term with a large (HAMT) map in an small + (FLAT) map could cause a critical error if the external + format was not produced by beam.</p> + <p> + Own Id: OTP-13125</p> + </item> + <item> + <p> + Fix very rare bug in GC when big maps with a lot of hash + collisions from a remote node are waiting in inner + message queue.</p> + <p> + Own Id: OTP-13146</p> + </item> + <item> + <p> + Fixed a bug that could cause a crash dump to become + almost empty.</p> + <p> + Own Id: OTP-13150</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> Updated the xmllint target to just check the xml + files with real documentation content.<br/> Corrected + some errors and added some missing target in the DTD's. + </p> + <p> + Own Id: OTP-13026</p> + </item> + <item> + <p> + Add function enif_getenv to read OS environment variables + in a portable way from NIFs.</p> + <p> + Own Id: OTP-13147</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.1</title> + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix bug in ETS that could cause stray objects marked for + deletion to occasionally be missed by the cleanup done by + <c>safe_fixtable(_,false)</c>.</p> + <p> + Own Id: OTP-12870</p> + </item> + <item> + <p> + Fixed VM crash that could occur if a trace port was + linked to a process, and the trace port terminated + abnormally while handling a trace message. This bug has + always existed in the runtime system with SMP support.</p> + <p> + Own Id: OTP-12901</p> + </item> + <item> + <p> + Instead of aborting, the vm now creates a crash dump when + a system process is terminated.</p> + <p> + Own Id: OTP-12934</p> + </item> + <item> + <p> + Fixed a rare emulator dead lock that occurred when + erlang:process_flag(priority,...) was called by a process + that was also scheduled for an internal system activity.</p> + <p> + Own Id: OTP-12943</p> + </item> + <item> + <p> + The runtime system on various posix platforms (except for + Linux and Solaris) could crash when large amounts of + file-descriptors were in use.</p> + <p> + Own Id: OTP-12954</p> + </item> + <item> + <p> + A beam file compiled by hipe for an incompatible runtime + system was sometimes not rejected by the loader, which + could lead to vm crash. This fix will also allow the same + hipe compiler to be used by both normal and debug-built + vm.</p> + <p> + Own Id: OTP-12962</p> + </item> + <item> + <p> + Fix bug in <c>maps:merge/2</c> when called by hipe + compiled code that could cause vm crash. Bug exists since + erts-7.0 (OTP 18.0).</p> + <p> + Own Id: OTP-12965</p> + </item> + <item> + <p> + When tracing with <c>process_dump</c> option, the VM + could abort if there was an ongoing binary match + somewhere in the call stack of the traced process.</p> + <p> + Own Id: OTP-12968</p> + </item> + <item> + <p> + Fixed possible output deadlock in tty driver when hitting + "CTRL-C" in a non-smp emulator shell on unix.</p> + <p> + Own Id: OTP-12987 Aux Id: Seq12947 </p> + </item> + <item> + <p> + Fix <c>binary_to_integer</c> to throw badarg for "+" and + "-" similar to <c>list_to_integer</c>.</p> + <p> + Own Id: OTP-12988</p> + </item> + <item> + <p> + Suppress warning of unused argument when using macro + enif_make_pid.</p> + <p> + Own Id: OTP-12989</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Changed default clock source used for OS system time on + MacOS X to <c>gettimeofday()</c> in order to improve + performance. The system can be configured during build to + use the previously used higher resolution clock source by + passing the switch <seealso + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP_Configuring"><c>--with-clock-resolution=high</c></seealso> + when configuring the build.</p> + <p> + Own Id: OTP-12945 Aux Id: OTP-12892 </p> + </item> + <item> + <p> + Added the <c>configure</c> option <seealso + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP_Configuring"><c>--disable-saved-compile-time</c></seealso> + which disables saving of compile date and time in the + emulator binary.</p> + <p> + Own Id: OTP-12971</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.0.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed a binary memory leak when printing to shell using + the tty driver (i.e. not -oldshell).</p> + <p> + Own Id: OTP-12941</p> + </item> + <item> + <p> + Fix a bug where the standard error port sometimes crashes + with eagain as the reason.</p> + <p> + Own Id: OTP-12942</p> + </item> + <item> + <p> + When tracing with <c>process_dump</c> option, the VM + could abort if there was an ongoing binary match + somewhere in the call stack of the traced process./</p> + <p> + Own Id: OTP-12968</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.0.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A process could end up in an inconsistent half exited + state in the runtime system without SMP support. This + could occur if the processes was traced by a port that it + also was linked to, and the port terminated abnormally + while handling a trace message for the process.</p> + <p> + This bug has always existed in the runtime system without + SMP support, but never in the runtime system with SMP + support.</p> + <p> + Own Id: OTP-12889 Aux Id: seq12885 </p> + </item> + <item> + <p> + Removed unnecessary copying of data when retrieving + corrected Erlang monotonic time.</p> + <p> + Own Id: OTP-12894</p> + </item> + <item> + <p> + Changed default OS monotonic clock source chosen at build + time. This in order to improve performance. The behavior + will now on most systems be that (both OS and Erlang) + monotonic time stops when the system is suspended.</p> + <p> + If you prefer that monotonic time elapse during suspend + of the machine, you can pass the command line argument + <c>--enable-prefer-elapsed-monotonic-time-during-suspend</c> + to <c>configure</c> when building Erlang/OTP. The + configuration stage will try to find such a clock source, + but might not be able to find it. Note that there might + be a performance penalty associated with such a clock + source.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12895</p> + </item> + <item> + <p> + <c>erlang:system_info(end_time)</c> returned a faulty + value on 32-bit architectures.</p> + <p> + Own Id: OTP-12896</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The <c>configure</c> command line argument + <c>--enable-gettimeofday-as-os-system-time</c> has been + added which force usage of <c>gettimeofday()</c> for OS + system time. This will improve performance of + <c>os:system_time()</c> and <c>os:timestamp()</c> on + MacOS X, at the expense of worse accuracy, resolution and + precision of Erlang monotonic time, Erlang system time, + and OS system time.</p> + <p> + Own Id: OTP-12892</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix a rare hanging of the VM seen to happen just after + emulator start. Bug exists since R14.</p> + <p> + Own Id: OTP-12859 Aux Id: seq12882 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 7.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix issuing with spaces and quoting in the arguments when + using erlang:open_port spawn_executable on windows. The + behavior now mimics how unix works. This change implies a + backwards incompatibility for how spawn_executable works + on windows.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-11905</p> + </item> + <item> + <p> + Fix global call trace when hipe compiled code call beam + compiled functions. Tracing of beam functions should now + alway work regardless who the caller is.</p> + <p> + Own Id: OTP-11939</p> + </item> + <item> + <p> + Correct cache alignment for ETS <c>write_concurrency</c> + locks to improve performance by reduced false sharing. + May increase memory footprint for tables with + <c>write_concurrency</c>.</p> + <p> + Own Id: OTP-11974</p> + </item> + <item> + <p> + All possibly blocking operations in the fd/spawn and + terminal driver have been converted to non-blocking + operations. Before this fix it was possible for the VM to + be blocked for a long time if the entity consuming + stdout/stderr did not consume it fast enough.</p> + <p> + Own Id: OTP-12239</p> + </item> + <item> + <p> + Add missing overhead for offheap binaries created from + external format. This fix can improve the garbage + collection of large binaries originating from + <c>binary_to_term</c> or messages from remote nodes.</p> + <p> + Own Id: OTP-12554</p> + </item> + <item> + <p> + Ensure hashing of zero is consistent</p> + <p> Erlang treats positive and negative zero as + equal:</p> + <p> + <c>true = 0.0 =:= 0.0/-1</c></p> + <p>However, Erlangs hash functions: hash, phash and + phash2 did not reflect this behaviour. The hash values + produced by the different hash functions would not be + identical for positive and negative zero.</p> <p>This + change ensures that hash value of positive zero is always + produced regardless of the signedness of the zero float, + i.e.,</p> + <p> + <c>true = erlang:phash2(0.0) =:= + erlang:phash2(0.0/-1)</c></p> + <p> + Own Id: OTP-12641</p> + </item> + <item> + <p> + Ensure NIF term creation disallows illegal floating point + values and too long atoms. Such values will cause a NIF + to throw badarg exception when it returns.</p> + <p> + Own Id: OTP-12655</p> + </item> + <item> + <p> + Fixed building of Map results from match_specs</p> + <p> + A faulty "box-value" entered into the heap which could + cause a segmentation fault in the garbage collector if it + was written on a heap fragment.</p> + <p> + Own Id: OTP-12656</p> + </item> + <item> + <p> + Fix hipe bug when matching a "writable" binary. The bug + has been seen to sometimes cause a failed binary matching + of a correct utf8 character, but other symptoms are also + possible.</p> + <p> + Own Id: OTP-12667</p> + </item> + <item> + <p> + Keep dirty schedulers from waking other schedulers.</p> + <p> + Own Id: OTP-12685</p> + </item> + <item> + <p> + Disable floating point exceptions if the VM is compiled + by clang/llvm. This is a known long-standing problem in + clang/llvm.</p> + <p> + Own Id: OTP-12717</p> + </item> + <item> + <p> + Fix bug in <c>file:sendfile</c> for FreeBSD causing not + the entire file to be sent.</p> + <p> + Own Id: OTP-12720</p> + </item> + <item> + <p> + Fix the broken Android support in erl_child_setup.c</p> + <p> + Own Id: OTP-12751</p> + </item> + <item> + <p> + Faulty statistics reported by the <c>fix_alloc</c> + allocator.</p> + <p> + Own Id: OTP-12766</p> + </item> + <item> + <p> + Fix two erts_snprintf() calls to correct sizes.</p> + <p> + - run_erl.c (ose): Use the size of the signal type, not + its pointer. - erl_node_tables.c: Use the size of the + _BUFFER in erts_snprintf() to make sure we can use the + full space.</p> + <p> + Own Id: OTP-12771</p> + </item> + <item> + <p> + Delayed memory allocations could be delayed an + unnecessarily long time.</p> + <p> + Own Id: OTP-12812</p> + </item> + <item> + <p> + Make sure that timeouts on a pool of acceptors are + released in the correct order.</p> + <p> + Own Id: OTP-12817</p> + </item> + <item> + <p> + Fix segmentation fault in module_info for deleted modules</p> + <p> + Own Id: OTP-12820</p> + </item> + <item> + <p>Fix garbage collection of literals in code purge</p> + <p>During code purging and check_process_code, the + checking of the binary reference embedded in the match + binary state was omitted for the tracing tests. This + would cause the binary match state to reference + deallocated memory.</p> + <p> + Own Id: OTP-12821</p> + </item> + <item> + <p> + A bug has been corrected for gen_tcp:close so when + {linger,{true,0}} is in effect it does not wait for data + in the driver queue to transfer out before closing the + port. Bug fix by Rory Byrne.</p> + <p> + Own Id: OTP-12840</p> + </item> + <item> + <p> + The documentation of the driver callback <seealso + marker="driver_entry#start"><c>start()</c></seealso> + erroneously stated that a return value of + <c>ERL_DRV_ERROR_ERRNO</c> caused the error value to be + passed via <c>erl_errno</c> when it should have been + <c>errno</c>.</p> + <p> + Own Id: OTP-12855</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Add <c>md5</c> and <c>module</c> entries to + <c>?MODULE:module_info/0/1</c> and remove obsolete entry + 'import'.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-11940</p> + </item> + <item> + <p> + Debug function <c>erlang:display/1</c> shows content of + binaries and bitstrings, not only the length.</p> + <p> + Own Id: OTP-11941</p> + </item> + <item> + <p>The time functionality of Erlang has been extended. + This both includes a <seealso + marker="time_correction#The_New_Time_API">new + API</seealso> for time, as well as <seealso + marker="time_correction#Time_Warp_Modes">time warp + modes</seealso> which alters the behavior of the system + when system time changes. <em>You are strongly encouraged + to use the new API</em> instead of the old API based on + <seealso + marker="erlang#now/0"><c>erlang:now/0</c></seealso>. + <c>erlang:now/0</c> has been deprecated since it is and + forever will be a scalability bottleneck. For more + information see the <seealso + marker="time_correction">Time and Time + Correction</seealso> chapter of the ERTS User's + Guide.</p> + <p>Besides the API changes and time warp modes a lot of + scalability and performance improvements regarding time + management has been made internally in the runtime + system. Examples of such improvements are scheduler + specific timer wheels, scheduler specific BIF timer + management, parallel retrieval of monotonic time and + system time on systems with primitives that are not + buggy.</p> + <p> + Own Id: OTP-11997</p> + </item> + <item> + <p><c>erlang:function_exported(M, F, A)</c> will now + return <c>true</c> if <c>M:F/A</c> refers to a BIF.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12099</p> + </item> + <item> + <p> + New BIF: <c>erlang:get_keys/0</c>, lists all keys + associated with the process dictionary. Note: + <c>erlang:get_keys/0</c> is auto-imported.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12151 Aux Id: seq12521 </p> + </item> + <item> + <p> + Make distributed send of large messages yield to improve + real-time characteristics.</p> + <p> + Own Id: OTP-12232</p> + </item> + <item> + <p> + Use high accuracy poll timeouts</p> + <p> + Where available, use poll/select API's that can handle + time resolutions less than 1ms. In the cases where such + API's are not available the timeout is rounded up to the + nearest ms.</p> + <p> + Own Id: OTP-12236</p> + </item> + <item> + <p> + The internal group to user_drv protocol has been changed + to be synchronous in order to guarantee that output sent + to a process implementing the user_drv protocol is + printed before replying. This protocol is used by the + standard_output device and the ssh application when + acting as a client. </p> + <p> + This change changes the previous unlimited buffer when + printing to standard_io and other devices that end up in + user_drv to 1KB.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12240</p> + </item> + <item> + <p>The previously introduced "eager check I/O" feature is + now enabled by default.</p> + <p>Eager check I/O can be disabled using the <c>erl</c> + command line argument: <seealso + marker="erl#+secio"><c>+secio false</c></seealso></p> + <p>Characteristics impact compared to previous + default:</p> <list> <item>Lower latency and smoother + management of externally triggered I/O operations.</item> + <item>A slightly reduced priority of externally triggered + I/O operations.</item> </list> + <p> + Own Id: OTP-12254 Aux Id: OTP-12117 </p> + </item> + <item> + <p> + Properly support maps in match_specs</p> + <p> + Own Id: OTP-12270</p> + </item> + <item> + <p> + The notice that a crashdump has been written has been + moved to be printed before the crashdump is generated + instead of afterwords. The wording of the notice has also + been changed.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12292</p> + </item> + <item> + <p> + New function <c>ets:take/2</c>. Works the same as + <c>ets:delete/2</c> but also returns the deleted + object(s).</p> + <p> + Own Id: OTP-12309</p> + </item> + <item> + <p> + Tracing with cpu_timestamp option has been enabled on + Linux.</p> + <p> + Own Id: OTP-12366</p> + </item> + <item> + <p> + ets:info/1,2 now contains information about whether + write_concurrency or read_concurrency is enabled.</p> + <p> + Own Id: OTP-12376</p> + </item> + <item> + <p> + Improved usage of <c>gcc</c>'s builtins for atomic memory + access. These are used when no other implementation of + atomic memory operations is available. For example, when + compiling for ARM when <c>libatomic_ops</c> is not + available.</p> + <p> + The largest improvement will be seen when compiling with + a <c>gcc</c> with support for the <c>__atomic_*</c> + builtins (using a <c>gcc</c> of at least version 4.7), + but also when only the legacy <c>__sync_*</c> builtins + are available (using a <c>gcc</c> of at least version + 4.1) an improvement can be seen.</p> + <p> + For more information see the "<seealso + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP_Configuring_Atomic-Memory-Operations-and-the-VM">Atomic + Memory Operations and the VM</seealso>" section of + <c>$ERL_TOP/HOWTO/INSTALL.md</c>.</p> + <p> + Own Id: OTP-12383</p> + </item> + <item> + <p> + Introduce <c>math:log2/1</c> function to math module.</p> + <p> + Own Id: OTP-12411</p> + </item> + <item> + <p>The documentation of the Abstract Format (in the ERTS + User's Guide) has been updated with types and + specification. (Thanks to Anthony Ramine.) </p> <p> The + explicit representation of parentheses used in types of + the abstract format has been removed. Instead the new + functions <c>erl_parse:type_inop_prec()</c> and + <c>erl_parse:type_preop_prec()</c> can be used for + inserting parentheses where needed. </p> + <p> + Own Id: OTP-12492</p> + </item> + <item> + <p> + Remove perfctr support</p> + <p> + Development of perfctr in the linux kernel ceased in + 2010. The perfctr support code in the Erlang VM is thus + effectively dead code and therefor removed.</p> + <p> + Own Id: OTP-12508</p> + </item> + <item> + <p><c>zlib:inflateChunk/2</c> has been added. It works + like <c>zlib:inflate/2</c>, but decompresses no more data + than will fit in the buffer configured by + <c>zlib:setBufSize/2</c>.</p> + <p> + Own Id: OTP-12548</p> + </item> + <item> + <p> + Use linear search for small select_val arrays</p> + <p> + Own Id: OTP-12555</p> + </item> + <item> + <p> + New BIF ets:update_counter/4 with a default object as + argument, which will be inserted in the table if the key + was not found.</p> + <p> + Own Id: OTP-12563</p> + </item> + <item> + <p> + Export missing types from zlib module</p> + <p> + Own Id: OTP-12584</p> + </item> + <item> + <p> + Use persistent hashmaps for large Maps</p> + <p>Maps will use a + persistent hashmap implementation when the number of + pairs in a Map becomes sufficiently large. The change + will occur when a Map reaches 33 pairs in size but this + limit might change in the future.</p> + <p>The most significant impact for the user by this + change is speed, and to a lesser degree memory + consumption and introspection of Maps. Memory consumption + size is probalistic but lesser than <c>gb_trees</c> or + <c>dict</c> for instance. Any other impacts will be + transparent for the user except for the following + changes.</p> + <p>Semantics of Maps have changed in two incompatible + ways compared to the experimental implementation in OTP + 17:</p> <list> <item>Hashing of maps is done different by + <c>erlang:phash2/1,2</c>, <c>erlang:phash/1</c> and + <c>erlang:hash/2</c>.</item> <item>Comparing two maps + with ==, /=, =<, <, >= and >, is done + different if the keys contain floating point + numbers.</item> </list> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12585</p> + </item> + <item> + <p> + Scalability improvement for <seealso + marker="erlang#make_ref/0">erlang:make_ref/0</seealso>, + and other functionality that create references. Each + scheduler now manage its own set of references. By this + no communication at all is needed when creating + references.</p> + <p> + Previous implementation generated a strictly + monotonically increasing sequence of references + corresponding to creation time on the runtime system + instance. This is <em>not</em> the case with current + implementation. You can only expect reference to be + unique. The Erlang/OTP documentation has never mentioned + anything else but the uniqueness property, so this change + <em>is</em> fully compatible. The only reason we've + marked this as a potential incompatibility is since an + early draft for an Erlang specification mentions strict + monotonicity as a property.</p> + <p> + If you need to create data with a strict monotonicity + property use <seealso + marker="erlang#unique_integer/1">erlang:unique_integer([monotonic])</seealso>. + Do <em>not</em> use the deprecated <seealso + marker="erlang#now/0">erlang:now()</seealso>.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12610</p> + </item> + <item> + <p> + Enable different abort signal from heart</p> + <p>By using environment variable HEART_KILL_SIGNAL, heart + can now use a different signal to kill the old running + Erlang.</p> + <p>By default the signal is SIGKILL but SIGABRT may also + be used by setting environment variable: + HEART_KILL_SIGNAL=SIGABRT</p> + <p> + Own Id: OTP-12613 Aux Id: seq12826 </p> + </item> + <item> + <p> + Update autconf to latest version 2015-03-04</p> + <p> + Own Id: OTP-12646</p> + </item> + <item> + <p> + Optimization of timers internally in the VM. This include + process timers (<c>receive ... after</c>), port timers + (<c>driver_set_timer()</c>) as well as BIF timers + (<c>erlang:send_after()</c>/<c>erlang:start_timer()</c>).</p> + <p> + Each scheduler thread now has its own lock-free timer + service instead of one locked central service. This + dramatically improves performance of timer management on + systems with a large amount of schedulers and timers.</p> + <p> + The timer service internal data structure has also been + optimized to be able to handle more timers than before. + That is, each timer service is by its self able to handle + more timers without dramatic performance loss than the + old centralized timer service.</p> + <p> + The API of BIF timers has also been extended. Timeout + values are for example no longer limited to 32-bit + integers. For more information see the documentation of + <seealso + marker="erlang#start_timer/4"><c>erlang:start_timer/4</c></seealso>, + <seealso + marker="erlang#send_after/4"><c>erlang:send_after/4</c></seealso>, + <seealso + marker="erlang#cancel_timer/2"><c>erlang:cancel_timer/2</c></seealso>, + and <seealso + marker="erlang#read_timer/2"><c>erlang:read_timer/2</c></seealso>.</p> + <p> + Characteristics impact: Calls to the synchronous versions + of <c>erlang:cancel_timer()</c>, and + <c>erlang:read_timer()</c> may take substantially longer + time to complete than before. This occur when the timer + that is accessed is managed by a remote scheduler. You + typically want to use the new asynchronous option in + order to avoid blocking the calling process.</p> + <p> + Own Id: OTP-12650 Aux Id: OTP-11997 </p> + </item> + <item> + <p> + Specialize instructions from common assembler patterns</p> + <p>Specialize common instructions of <c>rem</c>, + <c>band</c>, <c>minus</c> and <c>plus</c> in the beam + loader. This will reduce the number of fetches and thus + lessen the instruction dispatch pressure during runtime + and speed up those operations in some common cases.</p> + <p>Specialize move patterns from x-registers to the stack + with a new <c>move_window</c> instruction. This change + will reduce instruction dispatch pressure.</p> + <p> + Own Id: OTP-12690</p> + </item> + <item> + <p> + Fix cross compilation for Android.</p> + <p> + Own Id: OTP-12693</p> + </item> + <item> + <p> + Fix incorrect use of autoconf macro AC_EGREP_CPP, which + could cause faulty configuration if run from a path + containing the string 'yes'.</p> + <p> + Own Id: OTP-12706</p> + </item> + <item> + <p> + Minimal Java version is now 1.6</p> + <p> + Own Id: OTP-12715</p> + </item> + <item> + <p> + Send format and args on process exit to error_logger</p> + <p> + Previously, the emulator would generate a whole string + with values and call the error_logger passing + <c>"~s~n"</c>. This changes it to a format string + containing <c>~p</c> with the respective values as + arguments.</p> + <p> + Own Id: OTP-12735</p> + </item> + <item> + <p> + Map error logger warnings to warning messages by default.</p> + <p> + Own Id: OTP-12755</p> + </item> + <item> + <p> + Configure architecture ppc64le architecture as a ppc64</p> + <p> + Own Id: OTP-12761</p> + </item> + <item> + <p> + Add function <c>enif_raise_exception</c> to allow a NIF + to raise an error exception with any type of reason.</p> + <p> + Own Id: OTP-12770</p> + </item> + <item> + <p> + Optimized node table statistics retrieval.</p> + <p> + Own Id: OTP-12777</p> + </item> + <item> + <p> + Map beam error logger warnings to warning messages by + default. Previously these messages were mapped to the + error channel by default.</p> + <p> + Own Id: OTP-12781</p> + </item> + <item> + <p> + gen_tcp:shutdown/2 is now asynchronous</p> + <p> + This solves the following problems with the old + implementation:</p> + <p> + It doesn't block when the TCP peer is idle or slow. This + is the expected behaviour when shutdown() is called: the + caller needs to be able to continue reading from the + socket, not be prevented from doing so.</p> + <p> + It doesn't truncate the output. The current version of + gen_tcp:shutdown/2 will truncate any outbound data in the + driver queue after about 10 seconds if the TCP peer is + idle of slow. Worse yet, it doesn't even inform anyone + that the data has been truncated: 'ok' is returned to the + caller; and a FIN rather than an RST is sent to the TCP + peer.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12797</p> + </item> + <item> + <p> + Introduced delayed node table GC. This in order to avoid + oscillation of entries in and out of the tables. The + oscillation caused unnecessary lock contention on the + table locks. The delay length can be set by passing the + <seealso marker="erl#+zdntgc"><c>+zdntgc</c></seealso> + command line argument.</p> + <p> + Characteristics impact: The tables can grow to very large + sizes with unused entries if the node is get huge amounts + of short lived connections from other nodes. This problem + can be alleviated by shortening the length of the delay + using the <c>+zdntgc</c> command line argument.</p> + <p> + Own Id: OTP-12802</p> + </item> + <item> + <p>Improved implementation of <seealso + marker="erlang#statistics/1"><c>erlang:statistics</c></seealso><c>(io)</c> + in order to reduce contention between schedulers.</p> + <p>Characteristics impact: The actual call to + <c>erlang:statistics(io)</c> takes longer time to + complete, but the overall impact on the system is + improved.</p> + <p> + Own Id: OTP-12842</p> + </item> + <item> + <p> + There are many cases where user code needs to be able to + distinguish between a socket that was closed normally and + one that was aborted. Setting the option + {show_econnreset, true} enables the user to receive + ECONNRESET errors on both active and passive sockets.</p> + <p> + Own Id: OTP-12843</p> + </item> + <item> + <p> + Do not preallocate too large event pool</p> + <p> + A default pool size of 4000 is too excessive for the + common case. This corresponds directly to the number of + threads in the system. Change + ERTS_TS_EV_ALLOC_DEFAULT_POOL_SIZE to 2048. Change + ERTS_TS_EV_ALLOC_POOL_SIZE to 32.</p> + <p> + Own Id: OTP-12849</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.4.1.5</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed a bug that could cause a crash dump to become + almost empty.</p> + <p> + Own Id: OTP-13150</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.4.1.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The 'raw' socket option could not be used multiple times + in one call to any e.g gen_tcp function because only one + of the occurrences were used. This bug has been fixed, + and also a small bug concerning propagating error codes + from within inet:setopts/2.</p> + <p> + Own Id: OTP-11482 Aux Id: seq12872 </p> + </item> + </list> + </section> + +</section> + + +<section><title>Erts 6.4.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The VTS mode in Common Test has been modified to use a + private version of the Webtool application (ct_webtool).</p> + <p> + Own Id: OTP-12704 Aux Id: OTP-10922 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix missing quotation in the <c>LM_FIND_EMU_CC</c> + <c>autoconf</c> macro which could cause build failures.</p> + <p> + Own Id: OTP-12388</p> + </item> + <item> + <p> + Fix erroneous printout of monitors in crashdump file.</p> + <p> + Own Id: OTP-12537</p> + </item> + <item> + <p> + The runtime system without SMP support could crash in the + BIF <c>port_control/3</c> if the port that was being + accessed died during the call to the BIF.</p> + <p> + Own Id: OTP-12544 Aux Id: Seq12777 </p> + </item> + <item> + <p> + Avoid corrupt oversized integer to be created from binary + matching. Instead throw system_limit exception which is + the correct behavior. A peculiar symptom of this bug was + that bitwise operations (band, bor, bxor) on such + oversized integers could return the empty list []. + Credit: Mikael Pettersson, Nico Kruber</p> + <p> + Own Id: OTP-12556</p> + </item> + <item> + <p> + A race condition when calling <c>port_info/1</c> could + cause a memory fault has been fixed.</p> + <p> + Own Id: OTP-12587</p> + </item> + <item> + <p> + Fix comparison of exact terms. An overflow that could + cause faulty comparisons has been fixed. Comparison of + exact terms is exclusively used within Maps.</p> + <p> + Own Id: OTP-12623</p> + </item> + <item> + <p> + Fix bug in <c>list_to_integer/1</c> for very long lists + that could cause VM crash.</p> + <p> + Own Id: OTP-12624</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Introduced a runtime system internal 64-bit API for + atomic memory operations.</p> + <p> + Own Id: OTP-12351</p> + </item> + <item> + <p> + Add command line argument option for the initial size of + process dictionaries.</p> + <p> + Use '+hpds <size>' to set initial process + dictionary size for spawned processes.</p> + <p> + Own Id: OTP-12535 Aux Id: seq12809 </p> + </item> + <item> + <p> + Fix documentation on $char for Unicode</p> + <p> + Own Id: OTP-12545</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.3.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix getifaddrs realloc pointer error</p> + <p> + When a buffer was exhausted and subsequently reallocated, + we could get an unsafe pointer pointing to faulty memory.</p> + <p> + For this to occur we would need to have a large number of + interfaces and a reallocation of memory to a lower + addresses.</p> + <p> + The symptom would be garbage returned from + erlang:port_control(Port, 25, []) + (prim_inet:getifaddrs(Port) resulting in a badarg) or a + segmentation fault.</p> + <p> + Own Id: OTP-12445</p> + </item> + <item> + <p> + Don't close all file descriptors twice in child_setup</p> + <p> + The commit c2b4eab25c907f453a394d382c04cd04e6c06b49 + introduced an error in which child_setup erroneously + tried to close all file descriptors twice.</p> + <p> + Use closefrom() if available when closing all file + descriptors.</p> + <p> + The function closefrom() was only used in the vfork() + case before but is now also used in the fork() case if + available.</p> + <p> + Own Id: OTP-12446</p> + </item> + <item> + <p> + During a crashdump all file descriptors are closed to + ensure the closing of the epmd port and to reserve a file + descriptor for the crashdump file.</p> + <p> + If a driver (third party library) cannot handle closing + of sockets this could result in a segmentation fault in + which case a crashdump would not be produced. This is now + fixed by only closing inets sockets via an emergency + close callback to the driver and thus closing the epmd + socket.</p> + <p> + Own Id: OTP-12447</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix HiPE debug lock checking on OS X 64bit</p> + <p> + Position-independent code is mandatory on OS X. We use + r11 as an intermediate register to fill + BIF_P->hipe.bif_callee. This fixes the following error + when doing `make debug FLAVOR=smp`:</p> + <p> + clang -cc1as: fatal error: error in backend: 32-bit + absolute addressing is not supported in 64-bit mode</p> + <p> + Own Id: OTP-12188</p> + </item> + <item> + <p> + Fix race bug that could cause VM crash in + <c>erlang:port_get_data/1</c> if the port was closed by a + concurrent process. Also fix fatal bug if + <c>port_set_data/2</c> is called with a non-immediate + data term. Both bugs exist since R16B01.</p> + <p> + Own Id: OTP-12208</p> + </item> + <item> + <p> + Correct make variable SSL_DED_LD_RUNTIME_LIBRARY_PATH + when erl_xcomp_sysroot ends with a slash.</p> + <p> + Own Id: OTP-12216 Aux Id: seq12700 </p> + </item> + <item> + <p> + Fix two cases of unreachable code caused by false use of + assigment operators.</p> + <p> + Own Id: OTP-12222</p> + </item> + <item> + <p> + Fix bug when hipe compiled code makes tail call to a BIF + that disables GC while trapping (sush as binary_to_list, + list_to_binary, binary_to_term, term_to_binary).</p> + <p> + Own Id: OTP-12231</p> + </item> + <item> + <p> + Fix bug when a migrated empty memory carrier is reused + just before it should be destroyed by the thread that + created it.</p> + <p> + Own Id: OTP-12249</p> + </item> + <item> + <p> + Prevents compile-time errors in NIFs, when the compiler + is instructed to treat missing field initializers as + errors, by adding an initializer for the new options + field which was added to ErlNifEntry for 17.3.</p> + <p> + Own Id: OTP-12266</p> + </item> + <item> + <p> + Fixed CPU topology detection on FreeBSD systems where + Erlang/OTP is compiled by new C compilers (including, but + possibly not limited to, gcc 4.9 and clang).</p> + <p> + Own Id: OTP-12267</p> + </item> + <item> + <p> + Use C99 function isfinite() instead of finite() when + available on non GCC compilers.</p> + <p> + Own Id: OTP-12268</p> + </item> + <item> + <p> + Fix bug on windows where an incorrect number of links + could be returned when doing file:read_file_info on a + directory.</p> + <p> + Own Id: OTP-12269</p> + </item> + <item> + <p> + Fix rare bug when purging module on VM started with + +Meamin.</p> + <p> + Own Id: OTP-12273</p> + </item> + <item> + <p> + Repair run_erl terminal window size adjustment sent from + to_erl. This was broken in OTP 17.0 which could lead to + strange cursor behaviour in the to_erl shell.</p> + <p> + Own Id: OTP-12275 Aux Id: seq12739 </p> + </item> + <item> + <p> + Fixed bug on windows causing gen_tcp/udp to return an + error when given an fd to work with.</p> + <p> + Own Id: OTP-12289</p> + </item> + <item> + <p> + Fix various internal erts issues where negating a signed + integer in C would trigger undefined behavior. This fixes + issues when dividing with bignums and list_to_integer.</p> + <p> + Own Id: OTP-12290</p> + </item> + <item> + <p> + When flushing output to stdout on windows, the emulator + could sometimes hang indefinitely waiting for the flush + to complete. This has been fixed.</p> + <p> + Own Id: OTP-12291</p> + </item> + <item> + <p> + Fix so that non-smp emulators with dirty scheduler + support shows the correct number of dirty schedulers when + calling erlang:system_info(system_version).</p> + <p> + Own Id: OTP-12295</p> + </item> + <item> + <p> + Add <c>nif_version</c> to <c>erlang:system_info/1</c> in + order to get the NIF API version of the runtime system in + a way similar to <c>driver_version</c>.</p> + <p> + Own Id: OTP-12298</p> + </item> + <item> + <p> + Fix bug that could cause the return value from dirty NIF + with zero arity to be treated as garbage, leading to VM + crash.</p> + <p> + Own Id: OTP-12300</p> + </item> + <item> + <p> + Improve allocation carrier migration search logic. This + will reduce the risk of failed migrations that could lead + to excess memory consumption. It will also improve smp + performance due to reduced memory contention on the + migration pool.</p> + <p> + Own Id: OTP-12323</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p>Introduced support for eager check I/O.</p> + <p>By default eager check I/O will be disabled, but this + will most likely be changed in OTP 18. When eager check + I/O is enabled, schedulers will more frequently check for + I/O work. Outstanding I/O operations will however not be + prioritized to the same extent as when eager check I/O is + disabled.</p> + <p>Eager check I/O can be enabled using the <c>erl</c> + command line argument: <seealso + marker="erl#+secio"><c>+secio true</c></seealso></p> + <p>Characteristics impact when enabled:</p> <list> + <item>Lower latency and smoother management of externally + triggered I/O operations.</item> <item>A slightly reduced + priority of externally triggered I/O operations.</item> + </list> + <p> + Own Id: OTP-12117</p> + </item> + <item> + <p> + Fix erts .app-file</p> + <p> + Own Id: OTP-12189</p> + </item> + <item> + <p> + Add configure option --with-ssl-incl=PATH to support + OpenSSL installations with headers and libraries at + different places.</p> + <p> + Own Id: OTP-12215 Aux Id: seq12700 </p> + </item> + <item> + <p> + Optimization of atomic memory operations with release + barrier semantics on 32-bit PowerPC when using the + implementation included in OTP.</p> + <p> + Own Id: OTP-12250</p> + </item> + <item> + <p> + Minor adjustment of scheduler activation code making sure + that an activation of a scheduler is not prevented by its + run-queue being non-empty. (Thanks to Songlu Cai)</p> + <p> + Own Id: OTP-12287</p> + </item> + <item> + <p> + Improved support for atomic memory operations provided by + the <url + href="https://github.com/ivmai/libatomic_ops/">libatomic_ops</url> + library. Most importantly support for use of native + double word atomics when implemented by + <c>libatomic_ops</c> (for example, implemented for ARM).</p> + <p> + The <seealso + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP_Configuring_Atomic-Memory-Operations-and-the-VM"><c>$ERL_TOP/HOWTO/INSTALL.md</c></seealso> + document now also more clearly describes when you want to + build together with a <c>libatomic_ops</c> installation.</p> + <p> + Own Id: OTP-12302</p> + </item> + <item> + <p> + Add configure option --with-ssl-rpath to control which + runtime library path to use for dynamic linkage toward + OpenSSL.</p> + <p> + Own Id: OTP-12316 Aux Id: seq12753 </p> + </item> + <item> + <p> + Added systemd notify support to epmd</p> + <p> + Own Id: OTP-12321</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix bug when an migrated empty memory carrier is reused + just before it should be destroyed by the thread that + created it.</p> + <p> + Own Id: OTP-12249</p> + </item> + <item> + <p> + Repair run_erl terminal window size adjustment sent from + to_erl. This was broken in OTP 17.0 which could lead to + strange cursor behaviour in the to_erl shell.</p> + <p> + Own Id: OTP-12275 Aux Id: seq12739 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + General documentation updates.</p> + <p> + Own Id: OTP-12052</p> + </item> + <item> + <p>A bug in the VM code implementing sending of signals + to ports could cause the receiving port queue to remain + in a busy state forever. When this state had been + reached, processes sending command signals to the port + either got suspended forever, or, if the <c>nosuspend</c> + feature was used, always failed to send to the port. This + bug was introduced in ERTS version 5.10.</p> + <p>In order for this bug to be triggered on a port, one + had to at least once utilize the <c>nosuspend</c> + functionality when passing a signal to the port. This by + either calling</p> <list> <item> <seealso + marker="erlang#port_command/3"><c>port_command(Port, + Data, [nosuspend | Options])</c></seealso>, </item> + <item> <seealso + marker="erlang#send/3"><c>erlang:send(Port, {PortOwner, + {command, Data}}, [nosuspend | Options])</c></seealso>, + </item> <item> <seealso + marker="erlang#send_nosuspend/2"><c>erlang:send_nosuspend(Port, + {PortOwner, {command, Data}})</c></seealso>, or </item> + <item> <seealso + marker="erlang#send_nosuspend/3"><c>erlang:send_nosuspend(Port, + {PortOwner, {command, Data}}, Options)</c></seealso>. + </item> </list> + <p>Thanks Vasily Demidenok for reporting the issue, and + Sergey Kudryashov for providing a testcase.</p> + <p> + Own Id: OTP-12082 Aux Id: OTP-10336 </p> + </item> + <item> + <p> + Fix size overflow bug at memory allocation. A memory + allocation call, with an insane size close to the entire + address space, could return successfully as if it had + allocated just a few bytes. (Thanks to Don A. Bailey for + reporting)</p> + <p> + Own Id: OTP-12091</p> + </item> + <item> + <p> + Fix various issues where negating a signed integer would + trigger undefined behaviour. This fixes issues in the + enif_make_int64 interface and some edge cases inside the + erlang runtime system.</p> + <p> + Own Id: OTP-12097</p> + </item> + <item> + <p> + The documentation erroneously listed the <seealso + marker="erl#+swct"><c>+swct</c></seealso> command line + argument under <c>+sws</c>.</p> + <p> + Own Id: OTP-12102 Aux Id: OTP-10994 </p> + </item> + <item> + <p> + Profiling messages could be delivered out of order when + profiling on <c>runnable_procs</c> and/or + <c>runnable_ports</c> using <seealso + marker="erlang#system_profile/2"><c>erlang:system_profile/2</c></seealso>. + This bug was introduced in ERTS version 5.10.</p> + <p> + Own Id: OTP-12105 Aux Id: OTP-10336 </p> + </item> + <item> + <p> + Various logging fixes, including: Add run queue index to + the process dump in crash dumps.<br/> Add thread index to + enomem slogan when crashing.<br/> Remove error logger + message for sending messages to old instances of the same + node.</p> + <p> + Own Id: OTP-12115</p> + </item> + <item> + <p> + Fix compiler warnings reported by LLVM</p> + <p> + Own Id: OTP-12138</p> + </item> + <item> + <p> + Correct conversion of <c>MIN_SMALL</c> by + <c>list_to_integer/1</c> and <c>binary_to_integer/1</c>. + The bug produced an unnormalized bignum which can cause + strange behavior such as comparing different to a correct + <c>MIN_SMALL</c> integer. The value <c>MIN_SMALL</c> is + <c>-(1 bsl 27) = -134217728</c> on a 32-bit VM and <c>-(1 + bsl 59) = -576460752303423488</c> on a 64-bit VM. (Thanks + to Jesper Louis Andersen, Mikael Pettersson and Anthony + Ramine for report, patch and optimization suggestion)</p> + <p> + Own Id: OTP-12140</p> + </item> + <item> + <p> + Fix bug in <c>term_to_binary</c> that reallocates binary + with inconsistent size information. Bug has never been + confirmed to be the cause of any faulty behavior.</p> + <p> + Own Id: OTP-12141</p> + </item> + <item> + <p> + Real_path method used while prim loading archive files + was not taking into account the fact that windows + directory symlinks can be across different drives.</p> + <p> + Own Id: OTP-12155</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Add log2 histogram to lcnt for lock wait time</p> + <p> + Own Id: OTP-12059</p> + </item> + <item> + <p> + Introduced <seealso + marker="erl_nif#enif_schedule_nif"><c>enif_schedule_nif()</c></seealso> + to the NIF API.</p> + <p> + The <c>enif_schedule_nif()</c> function allows a + long-running NIF to be broken into separate NIF + invocations without the help of a wrapper function + written in Erlang. The NIF first executes part of the + long-running task, then calls <c>enif_schedule_nif()</c> + to schedule a NIF for later execution to continue the + task. Any number of NIFs can be scheduled in this manner, + one after another. Since the emulator regains control + between invocations, this helps avoid problems caused by + native code tying up scheduler threads for too long.</p> + <p> + The <c>enif_schedule_nif()</c> function also replaces the + <c>enif_schedule_dirty_nif()</c> in the experimental + dirty NIF API. Note that the only incompatible changes + made are in the experimental dirty NIF API.</p> + <p> + See the <seealso marker="erl_nif">NIF + documentation</seealso> for more information.</p> + <p> + Thanks to Steve Vinoski.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12128</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.1.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + OTP-11850 fixed filelib:wildcard/1 to work with broken + symlinks. This correction, however, introduced problems + since symlinks were no longer followed for functions like + filelib:ensure_dir/1, filelib:is_dir/1, + filelib:file_size/1, etc. This is now corrected.</p> + <p> + Own Id: OTP-12054 Aux Id: seq12660 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.1.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed ETHR_FORCE_INLINE which caused the build to break + on some platforms without adequate thread support + (VxWorks).</p> + <p> + Own Id: OTP-12010</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>The documentation for <c>spawn_opt/5</c> now has a + note mentioning that the <c>monitor</c> option is not + supported.</p> + <p> + Own Id: OTP-11849</p> + </item> + <item> + <p> + Fix broken system monitoring of <c>large_heap</c> for + non-smp VM. No message for <c>large_heap</c> was ever + sent on non-smp VM. Bug exist since R16B.</p> + <p> + Own Id: OTP-11852</p> + </item> + <item> + <p> + The emulator without SMP support crashed when passing a + message to a process without enough heap space for the + message. This bug was introduced in <c>erts-6.0</c>.</p> + <p> + Own Id: OTP-11887 Aux Id: OTP-11388 </p> + </item> + <item> + <p> + Fix race between ETS table deletion and unfixation that + could cause VM crash. The race could happen between a + terminating process that does not own the table but has a + fixation on it and another process that deletes the table + (maybe the owner terminating) at the same time. Bug + existed since R15B02.</p> + <p> + Own Id: OTP-11892</p> + </item> + <item> + <p>The string following the <c>-eval</c> option when + invoking <c>erl</c> would not be properly translated from + UTF-8 to a list of Unicode characters (as would the + arguments for <c>-run</c>).</p> + <p>That bug would cause the build of Erlang/OTP to fail + when building in a directory whose pathname contained + non-US ASCII characters encoded in UTF-8. (Thanks to Eric + Pailleau for reporting this bug.)</p> + <p> + Own Id: OTP-11916</p> + </item> + <item> + <p> + Fix erts_debug:size/1 to handle Map sizes</p> + <p> + Own Id: OTP-11923</p> + </item> + <item> + <p> + Removed <c>erlang:bitstr_to_list/1</c> and + <c>erlang:list_to_bitstr/1</c>. They were added by + mistake, and have always raised an <c>undefined</c> + exception when called.</p> + <p> + Own Id: OTP-11942</p> + </item> + <item> + <p> + Fixed compilation using mingw-w64 on Windows.</p> + <p> + Thanks to Jani Hakala.</p> + <p> + Own Id: OTP-11945</p> + </item> + <item> + <p> + The git sha is no longer printed in the shell start + header when erlang is built from a tagged git release.</p> + <p> + Own Id: OTP-11961</p> + </item> + <item> + <p> + Fixed a bug where <c>send</c> trace events were + erroneously dropped when the send was done to a + registered process. This bug was introduced in R16B.</p> + <p> + Own Id: OTP-11968</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p>The following native functions now bump an appropriate + amount of reductions and yield when out of + reductions:</p> <list> + <item><c>erlang:binary_to_list/1</c></item> + <item><c>erlang:binary_to_list/3</c></item> + <item><c>erlang:bitstring_to_list/1</c></item> + <item><c>erlang:list_to_binary/1</c></item> + <item><c>erlang:iolist_to_binary/1</c></item> + <item><c>erlang:list_to_bitstring/1</c></item> + <item><c>binary:list_to_bin/1</c></item> </list> + <p>Characteristics impact:</p> <taglist> + <tag>Performance</tag> <item>The functions converting + from lists got a performance loss for very small lists, + and a performance gain for very large lists.</item> + <tag>Priority</tag> <item>Previously a process executing + one of these functions effectively got an unfair priority + boost. This priority boost depended on the input size. + The larger the input was, the larger the priority boost + got. This unfair priority boost is now lost. </item> + </taglist> + <p> + Own Id: OTP-11888</p> + </item> + <item> + <p> + The systemd features of epmd have been removed from epmd + by default. To enable them you have to build erlang with + the configure option --enable-systemd.</p> + <p> + Own Id: OTP-11921</p> + </item> + <item> + <p> + Removed Erlang wrapper code used when calling + <c>binary_to_term/1</c>, and <c>binary_to_term/2</c>. + This improves the performance of these BIFs especially + when they are called with small binaries as input.</p> + <p> + Own Id: OTP-11931</p> + </item> + <item> + <p> + Add erlang:system_info(tolerant_timeofday), an API to + check whether compensation for sudden changes of system + time is enabled or not.</p> + <p> + Own Id: OTP-11970</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 6.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix broken system monitoring of <c>large_heap</c> for + non-smp VM. No message for <c>large_heap</c> was ever + sent on non-smp VM. Bug exist since R16B.</p> + <p> + Own Id: OTP-11852</p> + </item> + <item> + <p> + Fixed type spec of <c>erlang:system_info/1</c>.</p> + <p> + Own Id: OTP-11859 Aux Id: OTP-11615 </p> + </item> + </list> + </section> + +</section> + <section><title>Erts 6.0</title> <section><title>Fixed Bugs and Malfunctions</title> @@ -564,22 +2789,28 @@ <p> EEP43: New data type - Maps</p> <p> - With Maps you may for instance: <taglist> <item><c>M0 = - #{ a => 1, b => 2}, % create - associations</c></item> <item><c>M1 = M0#{ a := 10 }, % - update values</c></item> <item><c>M2 = M1#{ "hi" => - "hello"}, % add new associations</c></item> <item><c>#{ - "hi" := V1, a := V2, b := V3} = M2. % match keys with - values</c></item> </taglist></p> - <p> - For information on how to use Maps please see the - <seealso marker="doc/reference_manual:maps">Reference - Manual</seealso>.</p> + With Maps you may for instance:</p> + <taglist> + <tag/> <item><c>M0 = #{ a => 1, b => 2}, % create + associations</c></item> + <tag/><item><c>M1 = M0#{ a := 10 }, % update values</c></item> + <tag/><item><c>M2 = M1#{ "hi" => + "hello"}, % add new associations</c></item> + <tag/><item><c>#{ "hi" := V1, a := V2, b := V3} = M2. + % match keys with values</c></item> + </taglist> + <p> + For information on how to use Maps please see Map Expressions in the + <seealso marker="doc/reference_manual:expressions#map_expressions"> + Reference Manual</seealso>.</p> <p> The current implementation is without the following - features: <taglist> <item>No variable keys</item> - <item>No single value access</item> <item>No map - comprehensions</item> </taglist></p> + features:</p> + <taglist> + <tag/><item>No variable keys</item> + <tag/><item>No single value access</item> + <tag/><item>No map comprehensions</item> + </taglist> <p> Note that Maps is <em>experimental</em> during OTP 17.0.</p> <p> @@ -733,6 +2964,27 @@ Thanks to Matwey V. Kornilov</p> <p> Own Id: OTP-11829</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 5.10.4.1</title> + + <section><title>Known Bugs and Problems</title> + <list> + <item> + <p> + When using gen_tcp:connect and the <c>fd</c> option with + <c>port</c> and/or <c>ip</c>, the <c>port</c> and + <c>ip</c> options were ignored. This has been fixed so + that if <c>port</c> and/or <c>ip</c> is specified + together with <c>fd</c> a bind is requested for that + <c>fd</c>. If <c>port</c> and/or <c>ip</c> is not + specified bind will not be called.</p> + <p> + Own Id: OTP-12061</p> </item> </list> </section> @@ -2718,8 +4970,7 @@ <p> Fix erl_prim_loader errors in handling of primary archive. The following errors have been corrected:</p> - <p> - <list> <item> If primary archive was named "xxx", then a + <list> <item> If primary archive was named "xxx", then a file in the same directory named "xxxyyy" would be interpreted as a file named "yyy" inside the archive. </item> <item> erl_prim_loader did not correctly create @@ -2734,7 +4985,8 @@ erl_prim_loader:list_dir/1 would sometimes return an empty string inside the file list. This was a virtual element representing the top directory of the archive. - This has been removed. </item> </list></p> + This has been removed. </item> + </list> <p> Thanks to Tuncer Ayaz and Shunichi Shinohara for reporting and co-authoring corrections.</p> @@ -4831,7 +7083,7 @@ <item> <p> The <c>configure</c> command line argument <seealso - marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--enable-ethread-pre-pentium4-compatibility</seealso> + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--enable-ethread-pre-pentium4-compatibility</seealso> had no effect. This option is now also automatically enabled if required on the build machine.</p> <p> @@ -5177,12 +7429,12 @@ Own Id: OTP-8726 Aux Id: seq11617 </p> </item> <item> - <p>Fix libm linking with --as-needed flag + <p>Fix libm linking with --as-needed flag</p> <p> When building with "--as-needed" linker flags on Linux the build will fail. This has now been fixed.</p> <p> - (Thanks to Christian Faulhammer)</p></p> + (Thanks to Christian Faulhammer)</p> <p> Own Id: OTP-8728</p> </item> @@ -5410,7 +7662,7 @@ platforms than before. If <c>configure</c> warns about no atomic implementation available, try using the <c>libatomic_ops</c> library. Use the <seealso - marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--with-libatomic_ops=PATH</seealso> + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--with-libatomic_ops=PATH</seealso> <c>configure</c> command line argument when specifying where the <c>libatomic_ops</c> installation is located. The <c>libatomic_ops</c> library can be downloaded from: @@ -5428,7 +7680,7 @@ the pentium 4 processor. If you want the runtime system to be compatible with older processors (back to 486) you need to pass the <seealso - marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--enable-ethread-pre-pentium4-compatibility</seealso> + marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--enable-ethread-pre-pentium4-compatibility</seealso> <c>configure</c> command line argument when configuring the system.</p> <p> |