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-rw-r--r--erts/doc/src/Makefile1
-rw-r--r--erts/doc/src/alt_disco.xml93
-rw-r--r--erts/doc/src/erl.xml6
-rw-r--r--erts/doc/src/erl_driver.xml6
-rw-r--r--erts/doc/src/erlang.xml66
-rw-r--r--erts/doc/src/notes.xml25
-rw-r--r--erts/doc/src/part.xml1
7 files changed, 183 insertions, 15 deletions
diff --git a/erts/doc/src/Makefile b/erts/doc/src/Makefile
index 5fa8b0673a..96cc4413a9 100644
--- a/erts/doc/src/Makefile
+++ b/erts/doc/src/Makefile
@@ -74,6 +74,7 @@ XML_CHAPTER_FILES = \
match_spec.xml \
crash_dump.xml \
alt_dist.xml \
+ alt_disco.xml \
driver.xml \
absform.xml \
inet_cfg.xml \
diff --git a/erts/doc/src/alt_disco.xml b/erts/doc/src/alt_disco.xml
new file mode 100644
index 0000000000..d04221b9b3
--- /dev/null
+++ b/erts/doc/src/alt_disco.xml
@@ -0,0 +1,93 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE chapter SYSTEM "chapter.dtd">
+
+<chapter>
+ <header>
+ <copyright>
+ <year>2018</year><year>2018</year>
+ <holder>Ericsson AB. All Rights Reserved.</holder>
+ </copyright>
+ <legalnotice>
+ 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>
+
+ <title>How to Implement an Alternative Service Discovery for Erlang Distribution
+ </title>
+ <prepared>Timmo Verlaan</prepared>
+ <responsible></responsible>
+ <docno></docno>
+ <approved></approved>
+ <checked></checked>
+ <date>2018-04-25</date>
+ <rev>PA1</rev>
+ <file>alt_disco.xml</file>
+ </header>
+ <p>
+ This section describes how to implement an alternative discovery mechanism
+ for Erlang distribution. Discovery is normally done using DNS and the
+ Erlang Port Mapper Daemon (EPMD) for port discovery.
+ </p>
+
+ <note><p>
+ Support for alternative service discovery mechanisms was added in Erlang/OTP
+ 21.
+ </p></note>
+
+
+ <section>
+ <title>Introduction</title>
+ <p>To implement your own service discovery module you have to write your own
+ EPMD module. The <seealso marker="kernel:erl_epmd">EPMD module</seealso> is
+ responsible for providing the location of another node. The distribution
+ modules (<c>inet_tcp_dist</c>/<c>inet_tls_dist</c>) call the EPMD module to
+ get the IP address and port of the other node. The EPMD module that is part
+ of Erlang/OTP will resolve the hostname using DNS and uses the EPMD unix
+ process to get the port of another node. The EPMD unix process does this by
+ connecting to the other node on a well-known port, port 4369.</p>
+ </section>
+
+ <section>
+ <title>Discovery module</title>
+ <p>The discovery module needs to implement the same API as the regular
+ <seealso marker="kernel:erl_epmd">EPMD module</seealso>. However, instead of
+ communicating with EPMD you can connect to any service to find out
+ connection details of other nodes. A discovery module is enabled
+ by setting <seealso marker="erts:erl#epmd_module">-epmd_module</seealso>
+ when starting erlang. The discovery module must implement the following
+ callbacks:</p>
+
+ <taglist>
+ <tag><seealso marker="kernel:erl_epmd#start_link/0">start_link/0</seealso></tag>
+ <item>Start any processes needed by the discovery module.</item>
+ <tag><seealso marker="kernel:erl_epmd#names/1">names/1</seealso></tag>
+ <item>Return node names held by the registrar for the given host.</item>
+ <tag><seealso marker="kernel:erl_epmd#register_node/2">register_node/2</seealso></tag>
+ <item>Register the given node name with the registrar.</item>
+ <tag><seealso marker="kernel:erl_epmd#port_please/3">port_please/3</seealso></tag>
+ <item>Return the distribution port used by the given node.</item>
+ </taglist>
+
+ <p>The discovery module may implement the following callback:</p>
+
+ <taglist>
+ <tag><seealso marker="kernel:erl_epmd#address_please/3">address_please/3</seealso></tag>
+ <item><p>Return the address of the given node.
+ If not implemented, <seealso marker="kernel:inet#gethostbyname/1">
+ inet:gethostbyname/1</seealso> will be used instead</p>
+ <p>This callback may also return the port of the given node. In that case
+ <seealso marker="kernel:erl_epmd#port_please/3">port_please/3</seealso>
+ may be omitted.</p></item>
+ </taglist>
+ </section>
+</chapter>
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index 74654a295d..4cf0066999 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -631,14 +631,16 @@
of process heaps is destroyed by the crash dump generation.</p>
<p>Option <c>+d</c> instructs the emulator to produce only a
core dump and no crash dump if an internal error is detected.</p>
- <p>Calling <seealso marker="erlang:halt/1">
+ <p>Calling <seealso marker="erlang#halt/1">
<c>erlang:halt/1</c></seealso> with a string argument still
produces a crash dump. On Unix systems, sending an emulator process
a <c>SIGUSR1</c> signal also forces a crash dump.</p>
</item>
<tag><marker id="+e"/><c><![CDATA[+e Number]]></c></tag>
<item>
- <p>Sets the maximum number of ETS tables.</p>
+ <p>Sets the maximum number of ETS tables. This limit is
+ <seealso marker="stdlib:ets#max_ets_tables">partially obsolete</seealso>.
+ </p>
</item>
<tag><c><![CDATA[+ec]]></c></tag>
<item>
diff --git a/erts/doc/src/erl_driver.xml b/erts/doc/src/erl_driver.xml
index c790872fe4..e6c9905039 100644
--- a/erts/doc/src/erl_driver.xml
+++ b/erts/doc/src/erl_driver.xml
@@ -429,7 +429,7 @@
<taglist>
<tag>Return types for driver callbacks</tag>
<item>
- <p>Rrewrite driver callback
+ <p>Rewrite driver callback
<seealso marker="driver_entry#control"><c>control</c></seealso>
to use return type <c>ErlDrvSSizeT</c> instead of <c>int</c>.</p>
<p>Rewrite driver callback
@@ -841,7 +841,7 @@ int suggested_stack_size;</code>
<p>Thread options structure passed to
<seealso marker="#erl_drv_thread_create">
<c>erl_drv_thread_create</c></seealso>.
- The following fields exists:</p>
+ The following field exists:</p>
<taglist>
<tag><c>suggested_stack_size</c></tag>
<item>A suggestion, in kilowords, on how large a stack to use.
@@ -3220,6 +3220,6 @@ erl_drv_output_term(driver_mk_port(drvport), spec, sizeof(spec) / sizeof(spec[0]
<seealso marker="erlang"><c>erlang(3)</c></seealso>,
<seealso marker="kernel:erl_ddll"><c>erl_ddll(3)</c></seealso>,
section <seealso marker="alt_dist">How to Implement an Alternative
- Carrier for the Erlang Distribution></seealso> in the User's Guide</p>
+ Carrier for the Erlang Distribution</seealso> in the User's Guide</p>
</section>
</cref>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 3154fdaf8c..15bd80e72f 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -36,8 +36,8 @@
in this module. Some of the BIFs are viewed more
or less as part of the Erlang programming language and are
<em>auto-imported</em>. Thus, it is not necessary to specify the
- module name. For example, the calls <c>atom_to_list(Erlang)</c>
- and <c>erlang:atom_to_list(Erlang)</c> are identical.</p>
+ module name. For example, the calls <c>atom_to_list(erlang)</c>
+ and <c>erlang:atom_to_list(erlang)</c> are identical.</p>
<p>Auto-imported BIFs are listed without module prefix.
BIFs listed with module prefix are not auto-imported.</p>
@@ -7005,10 +7005,47 @@ ok
from other events in the system. It is only guaranteed that
<c><anno>Suspendee</anno></c> <em>eventually</em> suspends
(unless it
- is resumed). If option <c>asynchronous</c> has <em>not</em>
+ is resumed). If no <c>asynchronous</c> options has
been passed, the caller of <c>erlang:suspend_process/2</c> is
blocked until <c><anno>Suspendee</anno></c> has suspended.</p>
</item>
+ <tag><c>{asynchronous, ReplyTag}</c></tag>
+ <item>
+ <p>A suspend request is sent to the process identified by
+ <c><anno>Suspendee</anno></c>. When the suspend request
+ has been processed, a reply message is sent to the caller
+ of this function. The reply is on the form <c>{ReplyTag,
+ State}</c> where <c>State</c> is either:</p>
+ <taglist>
+ <tag><c>exited</c></tag>
+ <item>
+ <p>
+ <c><anno>Suspendee</anno></c> has exited.
+ </p>
+ </item>
+ <tag><c>suspended</c></tag>
+ <item>
+ <p>
+ <c><anno>Suspendee</anno></c> is now suspended.
+ </p>
+ </item>
+ <tag><c>not_suspended</c></tag>
+ <item>
+ <p>
+ <c><anno>Suspendee</anno></c> is not suspended.
+ This can only happen when the process that
+ issued this request, have called
+ <c>resume_process(<anno>Suspendee</anno>)</c>
+ before getting the reply.
+ </p>
+ </item>
+ </taglist>
+ <p>
+ Appart from the reply message, the <c>{asynchronous,
+ ReplyTag}</c> option behaves exactly the same as the
+ <c>asynchronous</c> option without reply tag.
+ </p>
+ </item>
<tag><c>unless_suspending</c></tag>
<item>
<p>The process identified by <c><anno>Suspendee</anno></c> is
@@ -7032,6 +7069,13 @@ ok
<warning>
<p>This BIF is intended for debugging only.</p>
</warning>
+ <warning>
+ <p>You can easily create deadlocks if processes suspends
+ each other (directly or in circles). In ERTS versions prior
+ to ERTS version 10.0, the runtime system prevented such
+ deadlocks, but this prevention has now been removed due
+ to performance reasons.</p>
+ </warning>
<p>Failures:</p>
<taglist>
<tag><c>badarg</c></tag>
@@ -8122,16 +8166,18 @@ ok
<c>erl(1)</c>.
</p>
</item>
+ <tag><marker id="system_info_ets_count"/>
+ <c>ets_count</c></tag>
+ <item>
+ <p>Returns the number of ETS tables currently existing at the
+ local node.</p>
+ </item>
<tag><marker id="system_info_ets_limit"/>
<c>ets_limit</c></tag>
<item>
- <p>Returns the maximum number of ETS tables allowed. This
- limit can be increased at startup by passing
- command-line flag
- <seealso marker="erts:erl#+e"><c>+e</c></seealso> to
- <c>erl(1)</c> or by setting environment variable
- <c>ERL_MAX_ETS_TABLES</c> before starting the Erlang
- runtime system.</p>
+ <p>Returns the limit for number of ETS tables. This limit is
+ <seealso marker="stdlib:ets#max_ets_tables">partially obsolete</seealso>
+ and number of tables are only limited by available memory.</p>
</item>
<tag><marker id="system_info_port_count"/><c>port_count</c></tag>
<item>
diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml
index 929d569f16..f7f86084a9 100644
--- a/erts/doc/src/notes.xml
+++ b/erts/doc/src/notes.xml
@@ -31,6 +31,31 @@
</header>
<p>This document describes the changes made to the ERTS application.</p>
+<section><title>Erts 9.3.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug in <c>enif_binary_to_term</c> which could cause
+ memory corruption for immediate terms (atoms, small
+ integers, pids, ports, empty lists).</p>
+ <p>
+ Own Id: OTP-15080</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:system_profile/2</c> that could
+ cause superfluous <c>{profile,_,active,_,_}</c> messages
+ for terminating processes.</p>
+ <p>
+ Own Id: OTP-15085</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Erts 9.3.1</title>
<section><title>Fixed Bugs and Malfunctions</title>
diff --git a/erts/doc/src/part.xml b/erts/doc/src/part.xml
index d583b873a0..fc39cb30e6 100644
--- a/erts/doc/src/part.xml
+++ b/erts/doc/src/part.xml
@@ -37,6 +37,7 @@
<xi:include href="match_spec.xml"/>
<xi:include href="crash_dump.xml"/>
<xi:include href="alt_dist.xml"/>
+ <xi:include href="alt_disco.xml"/>
<xi:include href="absform.xml"/>
<xi:include href="tty.xml"/>
<xi:include href="driver.xml"/>