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diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml index cdb72b2b98..de6696671b 100644 --- a/erts/doc/src/notes.xml +++ b/erts/doc/src/notes.xml @@ -30,6 +30,386 @@ </header> <p>This document describes the changes made to the ERTS application.</p> +<section><title>Erts 5.10</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Set new peeled off SCTP socket to nonblocking socket + (Thanks to Jonas Falkevik)</p> + <p> + Own Id: OTP-10491</p> + </item> + <item> + <p> + Fix various typos (thanks to Tuncer Ayaz)</p> + <p> + Own Id: OTP-10611</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + A boolean socket option 'ipv6_v6only' for IPv6 sockets + has been added. The default value of the option is OS + dependent, so applications aiming to be portable should + consider using <c>{ipv6_v6only,true}</c> when creating an + <c>inet6</c> listening/destination socket, and if + neccesary also create an <c>inet</c> socket on the same + port for IPv4 traffic. See the documentation.</p> + <p> + Own Id: OTP-8928 Aux Id: kunagi-193 [104] </p> + </item> + <item> + <p>It is now allowed to define stubs for BIFs, to allow + type specs to be written for BIFs. For example, if there + is BIF called <c>lists:member/2</c>, a dummy definition + of <c>lists:member/2</c> is now allowed.</p> + <p> + Own Id: OTP-9861</p> + </item> + <item> + <p> + Code loading and upgrade are now done without blocking + the emulator in single threaded mode. This will improve + realtime characteristics when code is loaded/upgraded on + a running SMP system.</p> + <p> + Own Id: OTP-9974</p> + </item> + <item> + <p>In the SMP emulator, turning on and off tracing will + no longer take down the system to single-scheduling. </p> + <p> + Own Id: OTP-10122</p> + </item> + <item> + <p> + Tuple funs (deprecated in R15B) are no longer supported.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10170</p> + </item> + <item> + <p>Major port improvements. The most notable:</p> <list> + <item>New internal port table implementation allowing for + both parallel reads as well as writes. Especially read + operations have become really cheap.</item> <item>Dynamic + allocation of port structures. This allow for a much + larger maximum amount of ports allowed as a default. The + previous default of 1024 has been raised to 65536. + Maximum amount of ports can be set using the <seealso + marker="erts:erl#+Q">+Q</seealso> command line flag of + <seealso marker="erts:erl">erl(1)</seealso>. The + previously used environment variable <c>ERL_MAX_PORTS</c> + has been deprecated and scheduled for removal in + OTP-R17.</item> <item>Major rewrite of scheduling of port + tasks. Major benefits of the rewrite are reduced + contention on run queue locks, and reduced amount of + memory allocation operations needed. The rewrite was also + necessary in order to make it possible to schedule + signals from processes to ports.</item> <item>Improved + internal thread progress functionality for easy + management of unmanaged threads. This improvement was + necessary for the rewrite of the port task + scheduling.</item> <item>Rewrite of all process to port + signal implementations in order to make it possible to + schedule those operations. All port operations can now be + scheduled which allows for reduced lock contention on the + port lock as well as truly asynchronous communication + with ports.</item> <item>Optimized lookup of port handles + from drivers.</item> <item>Optimized driver lookup when + creating ports.</item> <item>Preemptable <seealso + marker="erts:erlang#ports-0">erlang:ports/0</seealso> + BIF.</item> </list> + <p>These changes imply changes of the characteristics of + the system. The most notable:</p> <taglist> <tag>Order of + signal delivery.</tag> <item>The previous implementation + of the VM has delivered signals from processes to ports + in a synchronous stricter fashion than required by the + language. As of ERTS version 5.10, signals are truly + asynchronously delivered. The order of signal delivery + still adheres to the requirements of the language, but + only to the requirements. That is, some signal sequences + that previously always were delivered in one specific + order may now from time to time be delivered in different + orders. This may cause Erlang programs that have made + <em>false assumptions</em> about signal delivery order to + fail even though they previously succeeded. For more + information about signal ordering guarantees, see the + chapter on <seealso + marker="erts:communication">communication</seealso> in + the ERTS user's guide. The <seealso + marker="erts:erl#+n">+n</seealso> command line flag of + <seealso marker="erts:erl">erl(1)</seealso> can be + helpful when trying to find signaling order bugs in + Erlang code that have been exposed by these + changes.</item> <tag>Latency of signals sent from + processes to ports.</tag> <item>Signals from processes to + ports where previously always delivered immediately. This + kept latency for such communication to a minimum, but it + could cause lock contention which was very expensive for + the system as a whole. In order to keep this latency low + also in the future, most signals from processes to ports + are by default still delivered immediately as long as no + conflicts occur. Such conflicts include not being able to + acquire the port lock, but also include other conflicts. + When a conflict occur, the signal will be scheduled for + delivery at a later time. A scheduled signal delivery may + cause a higher latency for this specific communication, + but improves the overall performance of the system since + it reduce lock contention between schedulers. The default + behavior of only scheduling delivery of these signals on + conflict can be changed by passing the <seealso + marker="erts:erl#+spp">+spp</seealso> command line flag + to <seealso marker="erts:erl">erl(1)</seealso>. The + behavior can also be changed on port basis using the + <seealso + marker="erts:erlang#open_port_parallelism">parallelism</seealso> + option of the <seealso + marker="erts:erlang#open_port-2">open_port/2</seealso> + BIF.</item> <tag>Execution time of the + <c>erlang:ports/0</c> BIF.</tag> <item>Since <seealso + marker="erts:erlang#ports-0">erlang:ports/0</seealso> now + can be preempted, the responsiveness of the system as a + whole has been improved. A call to <c>erlang:ports/0</c> + may, however, take a much longer time to complete than + before. How much longer time heavily depends on the + system load.</item> </taglist> + <p><em>Potential incompatibilities</em>:</p> <list> + <item><c>driver_send_term()</c> has been deprecated and + has been scheduled for removal in OTP-R17. Replace usage + of <c>driver_send_term()</c> with usage of <seealso + marker="erts:erl_driver#erl_drv_send_term">erl_drv_send_term()</seealso>.</item> + <item><c>driver_output_term()</c> has been deprecated and + has been scheduled for removal in OTP-R17. Replace usage + of <c>driver_output_term()</c> with usage of <seealso + marker="erts:erl_driver#erl_drv_output_term">erl_drv_output_term()</seealso>.</item> + <item>The new function <seealso + marker="erts:erl_driver#erl_drv_busy_msgq_limits">erl_drv_busy_msgq_limits()</seealso> + has been added in order to able to control management of + port queues.</item> </list> + <p>The <seealso + marker="erts:erl_driver#version_management">driver API + version</seealso> has been bumped to 2.1 from 2.0 due to + the above changes in the driver API.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10336 Aux Id: kunagi-138 + [b5b97f67-fe34-46dc-93e6-a2931576db12] </p> + </item> + <item> + <p> + Erlang specification 4.7.3 defines max tuple size to + 65535 elements It is now enforced to no more than + 16777215 elements (arity 24 bits)</p> + <p> + Previous edge cases (28 bits) were not validated and + could cause undefined behaviour.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10633</p> + </item> + <item> + <p> + The previous default of a maximum of 32768 simultaneous + processes has been raised to 262144. This value can be + changed using the the <seealso + marker="erl#+P">+P</seealso> command line flag of + <seealso marker="erl">erl(1)</seealso>. Note that the + value passed now is considered as a hint, and that actual + value chosen in most cases will be a power of two.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10647 Aux Id: OTP-10336 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 5.9.3.1</title> + + <section><title>Known Bugs and Problems</title> + <list> + <item> + <p> + Create an erl_crash.dump if no heart exists and no + ERL_CRASH_DUMP_SECONDS is set (behaviour changed).</p> + <p> + Don't create an erl_crash.dump if heart do exists and no + ERL_CRASH_DUMP_SECONDS is set (behaviour not changed).</p> + <p> + This changes the behaviour back to the R15B02 default + considering if a beam was running with no heart.</p> + <p> + Own Id: OTP-10602</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 5.9.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix linking in OpenBSD. (Thanks to Matthew Dempsky)</p> + <p> + Own Id: OTP-10395</p> + </item> + <item> + <p> + Fix bug causing fallback atomics to be used even though + healthy gcc atomics or libatomic_ops was detected.</p> + <p> + Own Id: OTP-10418</p> + </item> + <item> + <p> + Ensure 'erl_crash.dump' when asked for it. This will + change erl_crash.dump behaviour.</p> + <p> + * Not setting ERL_CRASH_DUMP_SECONDS will now terminate + beam immediately on a crash without writing a crash dump + file.</p> + <p> + * Setting ERL_CRASH_DUMP_SECONDS to 0 will also terminate + beam immediately on a crash without writing a crash dump + file, i.e. same as not setting ERL_CRASH_DUMP_SECONDS + environment variable.</p> + <p> + * Setting ERL_CRASH_DUMP_SECONDS to a negative value will + let the beam wait indefinitely on the crash dump file + being written.</p> + <p> + * Setting ERL_CRASH_DUMP_SECONDS to a positive value will + let the beam wait that many seconds on the crash dump + file being written.</p> + <p> + A positive value will set an alarm/timeout for restart + both in beam and in heart if heart is running.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-10422 Aux Id: kunagi-250 [161] </p> + </item> + <item> + <p> + Fix bug where MSVRT100.dll was not included in the + windows installer.</p> + <p> + Own Id: OTP-10481</p> + </item> + <item> + <p>In the expression + <c><<Bin/binary,...>></c>, if <c>Bin</c> was + a bitstring with a size not a multiple of 8, either no + exception was generated or an incorrect exception was + generated. (Thanks to Adam Rutkowski for reporting this + bug.)</p> + <p> + Own Id: OTP-10524</p> + </item> + <item> + <p> + The runtime system could crash while scheduling a port + task. The port task was scheduled either due to an + external I/O event being triggered, a driver timeout + being triggered, or data being sent over a distribution + channel.</p> + <p> + Own Id: OTP-10556</p> + </item> + <item> + <p> + <c>erlang:memory(ets)</c> erroneously included the size + of each ETS-table main structure twice.</p> + <p> + Own Id: OTP-10558</p> + </item> + <item> + <p> + Fix compile error in generated file hipe_amd64_bifs.S for + Solaris.</p> + <p> + Own Id: OTP-10577</p> + </item> + <item> + <p> + A faulty spec for process_info/2 could cause false + dialyzer warnings. The spec is corrected.</p> + <p> + Own Id: OTP-10584</p> + </item> + <item> + <p> + In very rare cases, the VM could crash if a garbage + collector was called while executing an appending bit + syntax instruction. The symptom was a core when + reallocating memory in the function erts_bs_append. The + garbage collector bug is now corrected.</p> + <p> + Own Id: OTP-10590</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Improve support for building and testing in embedded ppc + environments.</p> + <p> + Own Id: OTP-10265 Aux Id: kunagi-159 + [daf97f67-5724-4812-a5b6-7e86990133d2-1] </p> + </item> + <item> + <p> + Due to a race condition on Windows, sometimes when + printing to standard output and then immediately + terminating erlang all data would not be printed. The + emulator now waits for all data to be printed before + exiting.</p> + <p> + Own Id: OTP-10325 Aux Id: kunagi-166 + [dd72d0e2-3e76-4a51-8b56-7564e24eecae] </p> + </item> + <item> + <p> + The frequency with which sleeping schedulers are woken + due to outstanding memory deallocation jobs has been + reduced.</p> + <p> + Own Id: OTP-10476 Aux Id: OTP-10162 </p> + </item> + <item> + <p> + Clearer warnings about the dangers of misuse of <seealso + marker="erl_nif#WARNING">native functions</seealso> and + <seealso marker="erl_driver#WARNING">drivers</seealso> + have been added to the documentation.</p> + <p> + Own Id: OTP-10557</p> + </item> + </list> + </section> + +</section> + <section><title>Erts 5.9.2</title> <section><title>Fixed Bugs and Malfunctions</title> |