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diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml index 2d96ed6105..4337d9d370 100644 --- a/erts/doc/src/notes.xml +++ b/erts/doc/src/notes.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2004</year><year>2013</year> + <year>2004</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -31,6 +31,1408 @@ </header> <p>This document describes the changes made to the ERTS application.</p> + +<section><title>Erts 8.0.2</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> + <item> + <p> + Fix VM abort "Overrun stack and heap" in garbage + collection triggered by a <c>bsl</c> operation and some + very specific heap conditions.</p> + <p> + Own Id: OTP-13732 Aux Id: seq13142 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 8.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A memory allocation bug in <c>group_leader/2</c> could + cause an emulator crash when garbage collecting a process + that had been assigned a remote group leader. This bug + was introduced in ERTS version 8.0.</p> + <p> + Own Id: OTP-13716</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 8.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>The handling of <c>on_load</c> functions has been + improved. The major improvement is that if a code upgrade + fails because the <c>on_load</c> function fails, the + previous version of the module will now be retained.</p> + <p> + Own Id: OTP-12593</p> + </item> + <item> + <p><c>is_builtin(erlang, apply, 3)</c> will now return + <c>true</c>.</p> + <p> + Own Id: OTP-13034</p> + </item> + <item> + <p> + Fix <c>enif_get_list_length</c> to return false if list + is improper or have length larger than <c>UINT_MAX</c> + (did return true and an incorrect length value).</p> + <p> + Own Id: OTP-13288 Aux Id: PR913 </p> + </item> + <item> + <p> + Cleanup hipe signal handling code for x86 and make it + more portable.</p> + <p> + Own Id: OTP-13341 Aux Id: PR951 </p> + </item> + <item> + <p> + Make file:datasync use fsync instead of fdatasync on Mac + OSX.</p> + <p> + Own Id: OTP-13411</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> + A bug has been fixed where if erlang was started +B on a + unix platform it would be killed by a SIGUSR2 signal when + creating a crash dump.</p> + <p> + Own Id: OTP-13425</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> + <item> + <p>Don't search for non-existing Map keys twice</p> + <p>For <c>maps:get/2,3</c> and <c>maps:find/2</c>, + searching for an immediate key, e.g. an atom, in a small + map, the search was performed twice if the key did not + exist.</p> + <p> + Own Id: OTP-13459</p> + </item> + <item> + <p> + When an abnormally large distribution message is about to + be sent, the VM has been changed to create a crash dump + instead of a core dump.</p> + <p> + Own Id: OTP-13474</p> + </item> + <item> + <p> + Fix <c>erlang:process_info/2</c> type specification</p> + <p> + Own Id: OTP-13485 Aux Id: ERL-123 </p> + </item> + <item> + <p> + Fix bug in <c>open_port/2</c> with option <c>{args, + List}</c>. A vm crash could be caused by an improper + <c>List</c>.</p> + <p> + Own Id: OTP-13489 Aux Id: ERL-127 </p> + </item> + <item> + <p> + Fixed a race-condition bug where the emulator could crash + when <c>erlang:system_profile/1,2</c> was enabled and a + process had to be re-scheduled during termination.</p> + <p> + Own Id: OTP-13494 Aux Id: ERL-126 </p> + </item> + <item> + <p> + Fixed bugs where the reduction counter was not handled + correct.</p> + <p> + Own Id: OTP-13512</p> + </item> + <item> + <p> + Fixed typo in description of the <c>EPMD_DUMP_REQ</c> + response.</p> + <p> + Own Id: OTP-13517</p> + </item> + <item> + <p> + Fixed a bug where a process flagged as sensitive would + sometimes record its save_calls when it shouldn't.</p> + <p> + Own Id: OTP-13540</p> + </item> + <item> + <p> + Update configure scripts to not use hard-coded path for + /bin/pwd and /bin/rm.</p> + <p> + Own Id: OTP-13562</p> + </item> + <item> + <p> + When passing a larger binary than the outputv callback of + a linked-in driver can handle in one io vector slot, the + binary is now split into multiple slots in the io vector. + This change only effects system where the max size of an + io vector slot is smaller then the word size of the + system (e.g. Windows).</p> + <p> + This change means that it is now possible on Windows to + send binaries that are larger than 4GB to port_command, + which is what is used for file:write, gen_tcp:send etc.</p> + <p> + Own Id: OTP-13628</p> + </item> + <item> + <p> + Workaround of Maps output in crashdumps. Currently the + atom 'undefined' is generated instead of Map data if a + Map type is encountered during crash.</p> + <p> + Own Id: OTP-13657</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The tracing support has been extended to allow a <seealso + marker="erl_tracer">tracer module</seealso> to be the + trace event handler instead of a process or port. The + <seealso marker="erl_tracer">tracer module</seealso> + makes it possible for trace tools to filter or manipulate + trace event data without the trace event first having to + be copied from the traced process or port.</p> + <p> + With the introduction of this feature, + <c>erlang:trace(all|existing, _, _)</c> now also returns + the tracer process as part of the number of processes on + which tracing is enabled. The is incompatible with the + previous releases.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10267</p> + </item> + <item> + <p> + Introduce LTTng tracing of Erlang Runtime System</p> + <p> + For LTTng to be enabled OTP needs to be built with + configure option <c>--with-dynamic-trace=lttng</c>.</p> + <p> + This feature introduces tracepoints for schedulers, + drivers, memory carriers, memory and async thread pool.</p> + <p> For a list of all tracepoints, see <seealso + marker="runtime_tools:LTTng">Runtime Tools User's + Guide</seealso> .</p> + <p> + Own Id: OTP-10282</p> + </item> + <item> + <p> + Make it possible to monitor/demonitor ports using the + <seealso + marker="erlang#monitor/2">erlang:monitor/2</seealso> API. + The process and port information functions have also been + updated to include information about monitors from + processes to ports.</p> + <p> + Own Id: OTP-11384</p> + </item> + <item> + <p> + Add microstate accounting</p> + <p> + Microstate accounting is a way to track which state the + different threads within ERTS are in. The main usage area + is to pin point performance bottlenecks by checking which + states the threads are in and then from there figuring + out why and where to optimize.</p> + <p> + Since checking whether microstate accounting is on or off + is relatively expensive only a few of the states are + enabled by default and more states can be enabled through + configure.</p> + <p> + There is a convenience module called msacc that has been + added to runtime_tools that can assist in gathering and + interpreting the data from Microstate accounting.</p> + <p> + For more information see <seealso + marker="erts:erlang#statistics_microstate_accounting">erlang:statistics(microstate_accounting, + _)</seealso> and the <seealso + marker="runtime_tools:msacc">msacc</seealso> module in + runtime_tools.</p> + <p> + Own Id: OTP-12345</p> + </item> + <item> + <p> + The port of Erlang/OTP to the real-time operating system + OSE has been removed.</p> + <p> + Own Id: OTP-12573</p> + </item> + <item> + <p> + Sharing preserved copy for messages and exit signals</p> + <p> + Enable sharing preserved copy with configure option + <c>--enable-sharing-preserving</c>. This will preserve + sharing, within the process, when communication with + other processes in the Erlang node. There is a trade-off, + the copy is more costly but this cost can be reclaimed if + there is a lot of sharing in the message. In addition + literals will not be copied in a send except during a + purge phase of the module where the literals are located. + This feature is considered experimental in 19.0.</p> + <p> + Own Id: OTP-12590 Aux Id: OTP-10251 </p> + </item> + <item> + <p> + Halfword BEAM has been removed.</p> + <p> + Own Id: OTP-12883</p> + </item> + <item> + <p> + Added <seealso + marker="kernel:os#perf_counter/1">os:perf_counter/1</seealso>.</p> + <p> + The perf_counter is a very very cheap and high resolution + timer that can be used to timestamp system events. It + does not have monoticity guarantees, but should on most + OS's expose a monotonous time.</p> + <p> + Own Id: OTP-12908</p> + </item> + <item> + <p> + Support for a fragmented young heap generation. That is, + the young heap generation can consist of multiple non + continuous memory areas. The main reason for this change + is to avoid extra copying of messages that could not be + allocated directly on the receivers heap.</p> + <p> + Own Id: OTP-13047</p> + </item> + <item> + <p> + Erlang linked-in driver can now force the call to + open_port to block until a call to erl_drv_init_ack is + made inside the driver. This is useful when you want to + do some asynchronous initialization, for example getting + configuration from a pipe, and you want the initial + open_port call to fail if the configuration is incomplete + or wrong. See the erl_driver documentation for more + details on the API.</p> + <p> + Own Id: OTP-13086</p> + </item> + <item> + <p> + Erlang linked-in drivers can now set their own pids as + seen in <c>erlang:port_info/1</c> by using the + <c>erl_drv_set_pid</c> function. For more details see the + erl_driver documentation.</p> + <p> + Own Id: OTP-13087</p> + </item> + <item> + <p> + The functionality behind <c>erlang:open_port/2</c> when + called with spawn or spawn_executable has been redone so + that the forking of the new program is done in a separate + process called erl_child_setup. This allows for a much + more robust implementation that uses less memory and does + not block the entire emulator if the program to be + started is on an un-accessible NFS. Benchmarks have shown + this approach to be about 3-5 times as fast as the old + approach where the fork/vfork was done by erts. This is a + pure stability and performance fix, however some error + messages may have changed, which is why it is marked as a + backwards incompatible change.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-13088</p> + </item> + <item> + <p>Improved yielding strategy in the implementation of + the following native functions:</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>This + in order to improve performance of these functions.</p> + <p> + Own Id: OTP-13096</p> + </item> + <item> + <p> + All garbage collections of processes now bump reductions. + Also the amount of reductions bumped when garbage + collecting has been adjusted. It now better corresponds + to the amount of work performed. This in order to improve + the real time characteristics of the system.</p> + <p> + Own Id: OTP-13097</p> + </item> + <item> + <p>New functions that can load multiple modules at once + have been added to the '<c>code</c>' module. The + functions are <c>code:atomic_load/1</c>, + <c>code:prepare_loading/1</c>, + <c>code:finish_loading/1</c>, and + <c>code:ensure_modules_loaded/1</c>.</p> + <p> + Own Id: OTP-13111</p> + </item> + <item> + <p>The <c>-boot_var</c> option for <c>erl</c> now only + supports a single key and single value (as documented). + The option used to allow multiple key/value pairs, but + that behavior was undocumented.</p> + <p>The function <c>erl_prim_loader:start/3</c> has been + removed. Its documentation has also been removed.</p> + <p>The undocumented and unsupported function + <c>erl_prim_loader:get_files/2</c> has been removed.</p> + <p> + Own Id: OTP-13112</p> + </item> + <item> + <p> + Low level BIF <c>erlang:purge_module/1</c> is made more + robust against incorrect use. Lingering processes that + still refer the old code are now killed before the module + is purged to prevent fatal VM behavior.</p> + <p> + Own Id: OTP-13122</p> + </item> + <item> + <p>Improved dirty scheduler implementation. For more + information see the <seealso + marker="erl_nif#dirty_nifs">NIF + documentation</seealso>.</p> <note><list> <item><p>The + dirty scheduler support is still + <em>experimental</em>.</p></item> <item><p>The support + for determining whether dirty NIF support exist or not at + compile time using the C preprocessor macro + <c>ERL_NIF_DIRTY_SCHEDULER_SUPPORT</c> has been + removed.</p></item> <item><p>The + <c>enif_is_on_dirty_scheduler()</c> function has been + removed. Use <seealso + marker="erl_nif#enif_thread_type"><c>enif_thread_type()</c></seealso> + instead.</p></item> </list></note> + <p> + Own Id: OTP-13123</p> + </item> + <item> + <p> + Various optimizations done to process dictionary access.</p> + <p> + Own Id: OTP-13167</p> + </item> + <item> + <p> + Added max_heap_size process flag. max_heap_size allows + the user to limit the maximum heap used by a process. See + <seealso + marker="erlang#process_flag/2">erlang:process_flag</seealso> + for more details.</p> + <p> + Own Id: OTP-13174</p> + </item> + <item> + <p> + Allow dynamic drivers and NIF libraries to be built with + gcc option <c>-fvisibility=hidden</c> for faster loading + and more optimized code.</p> + <p> + Own Id: OTP-13227</p> + </item> + <item> + <p> + Add <c>erlang:process_info(Pid, + garbage_collection_info)</c> which returns extended + garbage_collection information. For more details see the + documentation.</p> + <p> + Own Id: OTP-13265</p> + </item> + <item> + <p> + The functions <c>erlang:list_to_integer/1</c> and + <c>string:to_integer/1</c> have been optimized for large + inputs.</p> + <p> + Own Id: OTP-13293</p> + </item> + <item> + <p> + Improved memory allocation strategy for hipe native code + on x86_64 (amd64) architectures by reserving enough low + virtual address space needed for the HiPE/AMD64 small + code model. The default virtual address area for hipe + code is set to 512Mb, but can be changed with emulator + flag <c>+MXscs</c>.</p> + <p> + Own Id: OTP-13359</p> + </item> + <item> + <p> + Introduction of configurable management of data referred + to by the message queue of a process. Each process can be + configured individually.</p> + <p> + It is now possible to configure the message queue of a + process, so that all data referred by it will be kept + outside of the heap, and by this prevent this data from + being part of garbage collections.</p> + <p> + For more information see the documentation of <seealso + marker="erlang#process_flag_message_queue_data"><c>process_flag(message_queue_data, + MQD)</c></seealso>.</p> + <p> + Own Id: OTP-13366 Aux Id: OTP-13047 </p> + </item> + <item> + <p> + Processes now yield when scanning large message queues + and not finding a matching message. This in order to + improve real time characteristics.</p> + <p> + Own Id: OTP-13401</p> + </item> + <item> + <p> + Optimized an erts internal function that is used to + traverse erlang terms. The internal function was mainly + used by term_to_binary and comparison of terms. + Benchmarks have shown up to a 10% performance increase in + those functions after the optimization.</p> + <p> + Own Id: OTP-13440</p> + </item> + <item> + <p> + Add the following NIF API functions:</p> + <p> + <list> <item><seealso + marker="erl_nif#enif_cpu_time"><c>enif_cpu_time</c></seealso></item> + <item><seealso + marker="erl_nif#enif_now_time"><c>enif_now_time</c></seealso></item> + <item><seealso + marker="erl_nif#enif_make_unique_integer"><c>enif_make_unique_integer</c></seealso></item> + <item><seealso + marker="erl_nif#enif_is_process_alive"><c>enif_is_process_alive</c></seealso></item> + <item><seealso + marker="erl_nif#enif_is_port_alive"><c>enif_is_port_alive</c></seealso></item> + <item><seealso + marker="erl_nif#enif_term_to_binary"><c>enif_term_to_binary</c></seealso></item> + <item><seealso + marker="erl_nif#enif_binary_to_term"><c>enif_binary_to_term</c></seealso></item> + <item><seealso + marker="erl_nif#enif_port_command"><c>enif_port_command</c></seealso></item> + </list></p> + <p> + for details of what each function does, see the erl_nif + documentation.</p> + <p> + Own Id: OTP-13442</p> + </item> + <item> + <p> + Optimize <c>'++'</c> operator and <c>lists:append/2</c> + by using a single pass to build a new list while checking + for properness.</p> + <p> + Own Id: OTP-13487</p> + </item> + <item> + <p> + Handle terms (pids,ports and refs) from nodes with a + 'creation' value larger than 3. This is a preparation of + the distribution protocol to allow OTP 19 nodes to + correctly communicate with future nodes (20 or higher). + The 'creation' value differentiates different + incarnations of the same node (name).</p> + <p> + Own Id: OTP-13488</p> + </item> + <item> + <p> + Don't send unasked for systemd notifications in epmd</p> + <p> + Own Id: OTP-13493 Aux Id: PR-999 </p> + </item> + <item> + <p> + The enif_send API has been extended to allow NULL to be + used as the message environment. When used this way, a + message environment is implicitly created and the given + term is copied into that environment before sending. This + can be an optimization if many small messages are being + sent by the nif.</p> + <p> + Own Id: OTP-13495</p> + </item> + <item> + <p> + The tracing support has been extended to allow tracing on + ports. Ports can be traced on using the 'ports', 'send' + and 'receive' trace flags.</p> + <p> + The first argument of <seealso + marker="erts:erlang#trace/3">erlang:trace/3</seealso> has + been extended so that <c>'all'</c>, <c>'existing'</c> and + <c>'new'</c> now include both processes and ports. New + <c>Tracee</c> variants, <c>'all_processes'</c>, + <c>'all_ports'</c>, <c>'existing_processes'</c> etc have + been added to specify only processes or ports.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-13496</p> + </item> + <item> + <p> + When the <c>'procs'</c> trace flag is enabled, a + <c>'spawned'</c> trace event is now also generated by a + newly created process. The previous event <c>'spawn'</c> + remains, but as it is generated by the process that did + the spawn, it is not guaranteed that it is ordered with + other trace events from the newly spawned process. So + when tracking the lifetime of a process this new event + should be used as the creation event.</p> + <p> + This new trace event is marked as an incompatibility + because tools that expect certain trace events when + enabling 'procs' will have to updated.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-13497</p> + </item> + <item> + <p> + Add the <seealso + marker="erts:erlang#match_spec_test/3">erlang:match_spec_test/3</seealso> + function. The functions allows the testing of match + specifications for both tracing and ets tables. It can be + used to test that a match specification does the expected + filtering on specific data. It also returns more verbose + error reasons for incorrectly constructed match + specifications.</p> + <p> + Own Id: OTP-13501</p> + </item> + <item> + <p> + The erts internal tracing support has been changed to + have much less overhead and be more scalable.</p> + <p> + This rewrite does not break any backwards + incompatibilities, but it does change the ordering of + some trace messages when compared to previous releases. + It should be noted that this only applies to trace + messages sent to processes or ports, it does not apply to + the new tracer module. However in future releases they + may also be effected by this.</p> + <p> + Trace messages are only guaranteed to be ordered from one + traced process or port. In previous releases this was not + visible as a <c>'send'</c> trace message would always + arrive before the corresponding <c>'receive'</c> trace + message that is no longer always the case. This also + means that timestamped trace messages may seem to arrive + out of order as the timestamp is taken when the event is + triggered and not when it is put in the queue of the + tracer.</p> + <p> + Own Id: OTP-13503</p> + </item> + <item> + <p> + Add possibility to filter <c>send</c> and <c>receive</c> + trace with match specifications.</p> + <p> + Own Id: OTP-13507</p> + </item> + <item> + <p> + Add <c>maps:update_with/3,4</c> and <c>maps:take/2</c></p> + <p> + Own Id: OTP-13522 Aux Id: PR-1025 </p> + </item> + <item> + <p> + Introduce LTTng tracing via Erlang tracing.</p> + <p> + For LTTng to be enabled OTP needs to be built with + configure option <c>--with-dynamic-trace=lttng</c>.</p> + <p>The dynamic trace module <c>dyntrace</c> is now + capable to be used as a LTTng sink for Erlang tracing. + For a list of all tracepoints, see <seealso + marker="runtime_tools:LTTng">Runtime Tools User's + Guide</seealso> .</p> + <p>This feature also introduces an incompatible change in + trace tags. The trace tags <c>gc_start</c> and + <c>gc_end</c> has been split into <c>gc_minor_start</c>, + <c>gc_minor_end</c> and <c>gc_major_start</c>, + <c>gc_major_end</c>.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-13532</p> + </item> + <item> + <p> + Print heap pointers for garbing processes during + crashdump</p> + <p> + Own Id: OTP-13541 Aux Id: PR-1026 </p> + </item> + <item> + <p> + Changed and improved low level memory statistics returned + by <c>erlang:system_info/1</c>. The info for + <c>erts_mmap</c> has been moved from <c>mseg_alloc</c> to + its own section returned by <c>{allocator, + erts_mmap}</c>.</p> + <p> + Own Id: OTP-13560</p> + </item> + <item> + <p> + Add enif_snprintf to the NIF API</p> + <p> + The function <c>enif_snprintf</c> is similar to + <c>snprintf</c> call but can handle formatting of Erlang + terms via <c>%T</c> format specifier.</p> + <p> + Own Id: OTP-13580</p> + </item> + <item> + <p>The warning in the documentation for + <c>erlang:raise/3</c> has been removed. It is now + officially perfectly fine to use raise/3 in production + code.</p> + <p> + Own Id: OTP-13599</p> + </item> + <item> + <p> + Fix bugs caused by the VM sometimes truncating object + sizes or offsets to 32 bits on 64-bit hosts. These bugs + were mainly found when working with large unicode strings + and nifs environments.</p> + <p> + Own Id: OTP-13606</p> + </item> + <item> + <p> + Add <c>-start_epmd</c> command line option, this lets you + disable automatic starting of epmd when starting a + distributed node.</p> + <p> + Add <c>-epmd_module</c> command line option, this lets + you specify a module to register and look-up node names + in. The default module is <c>erl_epmd</c>.</p> + <p> + Own Id: OTP-13627</p> + </item> + <item> + <p> + <c>erlang:halt</c> now truncates strings longer than 200 + characters instead of failing with <c>badarg</c>.</p> + <p> + Own Id: OTP-13630</p> + </item> + <item> + <p> + Fix possible race in poller wake up on windows</p> + <p> + Own Id: OTP-13634</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> @@ -462,19 +1864,20 @@ </item> <item> <p> - Use persistent hashmaps for large Maps <p>Maps will use a + 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> - <p>The most significant impact for the user by 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 + <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 @@ -734,6 +2137,42 @@ </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> @@ -1122,7 +2561,7 @@ <p> Improved support for atomic memory operations provided by the <url - href="https://github.com/ivmai/libatomic_ops/"><c>libatomic_ops</c></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> @@ -2089,22 +3528,28 @@ <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> + 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> @@ -4264,8 +5709,7 @@ <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 @@ -4280,7 +5724,8 @@ 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> @@ -6723,12 +8168,12 @@ 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> |