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-rw-r--r--erts/doc/src/erl.xml60
1 files changed, 48 insertions, 12 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index f7d8d37fd3..85c6140b01 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -586,18 +586,38 @@
<seealso marker="erts_alloc">erts_alloc(3)</seealso> for
further information.</p>
</item>
- <tag><c><![CDATA[+n]]></c></tag>
- <item>
- <p>Enable synchronous message passing to ports.</p>
- <p>As of OTP-R16 message passing to ports are truly asynchronously
- implemented. Correctly written Erlang programs should be able
- to handle this without any issues. Bugs in existing Erlang
- programs that make false assumptions about message passing to
- ports may, however, be tricky to find. This switch has been
- introduced in order to at least make it easier to compare
- behaviors during a transition period. Note that this flag is
- deprecated as of its introduction, and is scheduled for removal
- in OTP-R17.</p>
+ <tag><c><![CDATA[+n Behavior]]></c></tag>
+ <item>
+ <p>Control behavior of signals to ports.</p>
+ <p>As of OTP-R16 signals to ports are truly asynchronously
+ delivered. Note that signals always have been documented as
+ asynchronous. The underlying implementation has, however,
+ previously delivered these signals synchronously. Correctly
+ written Erlang programs should be able to handle this without
+ any issues. Bugs in existing Erlang programs that make false
+ assumptions about signals to ports may, however, be tricky to
+ find. This switch has been introduced in order to at least
+ make it easier to compare behaviors during a transition period.
+ Note that <em>this flag is deprecated</em> as of its
+ introduction, and is scheduled for removal in OTP-R17.
+ <c>Behavior</c> should be one of the following characters:</p>
+ <taglist>
+ <tag><c>d</c></tag>
+ <item>The default. Asynchronous signals. A process that sends
+ a signal to a port may continue execution before the signal
+ has been delivered to the port.</item>
+ <tag><c>s</c></tag>
+ <item>Synchronous signals. A processes that sends a signal
+ to a port will not continue execution until the signal has
+ been delivered. Should <em>only</em> be used for testing and
+ debugging.</item>
+ <tag><c>a</c></tag>
+ <item>Asynchronous signals. As the default, but a processes
+ that sends a signal will even more frequently continue
+ execution before the signal has been delivered to the
+ port. Should <em>only</em> be used for testing and
+ debugging.</item>
+ </taglist>
</item>
<tag><marker id="max_processes"><c><![CDATA[+P Number]]></c></marker></tag>
<item>
@@ -948,6 +968,22 @@
without prior notice.
</p>
</item>
+ <tag><marker id="+spp"><c>+spp Bool</c></marker></tag>
+ <item>
+ <p>Set default scheduler hint for port parallelism. If set to
+ <c>true</c>, the VM will schedule port tasks when it by this can
+ improve the parallelism in the system. If set to <c>false</c>,
+ the VM will try to perform port tasks immediately and by this
+ improve latency at the expense of parallelism. If this
+ flag has not been passed, the default scheduler hint for port
+ parallelism is currently <c>false</c>. The default used can be
+ inspected in runtime by calling
+ <seealso marker="erlang#system_info_port_parallelism">erlang:system_info(port_parallelism)</seealso>.
+ The default can be overriden on port creation by passing the
+ <seealso marker="erlang#open_port_parallelism">parallelism</seealso>
+ option to
+ <seealso marker="erlang#open_port/2">open_port/2</seealso></p>.
+ </item>
<tag><marker id="sched_thread_stack_size"><c><![CDATA[+sss size]]></c></marker></tag>
<item>
<p>Suggested stack size, in kilowords, for scheduler threads.