diff options
Diffstat (limited to 'erts/doc/src')
| -rw-r--r-- | erts/doc/src/erl.xml | 67 | ||||
| -rw-r--r-- | erts/doc/src/erlang.xml | 35 |
2 files changed, 75 insertions, 27 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index 4ef3e089a6..f7d8d37fd3 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -586,13 +586,51 @@ <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> + </item> <tag><marker id="max_processes"><c><![CDATA[+P Number]]></c></marker></tag> <item> - <p>Sets the maximum number of concurrent processes for this - system. <c><![CDATA[Number]]></c> must be in the range 16..134217727. - Default is 32768.</p> - <p><em>NOTE</em>: It is possible to choose any value in the range - but powers of 2 perform best.</p> + <p>Sets the maximum number of simultaneously existing processes for this + system. Valid range for <c>Number</c> is <c>[1024-134217727]</c></p> + <p><em>NOTE</em>: The actual maximum chosen may be much larger than + the <c>Number</c> passed. Currently the runtime system often, + but not always, chooses a value that is a power of 2. This might, + however, be changed in the future. The actual value chosen can be + checked by calling + <seealso marker="erlang#system_info_process_limit">erlang:system_info(process_limit)</seealso>.</p> + <p>The default value is <c>262144</c></p> + </item> + <tag><marker id="max_ports"><c><![CDATA[+Q Number]]></c></marker></tag> + <item> + <p>Sets the maximum number of simultaneously existing ports for this + system. Valid range for <c>Number</c> is <c>[1024-134217727]</c></p> + <p><em>NOTE</em>: The actual maximum chosen may be much larger than + the actual <c>Number</c> passed. Currently the runtime system often, + but not always, chooses a value that is a power of 2. This might, + however, be changed in the future. The actual value chosen can be + checked by calling + <seealso marker="erlang#system_info_port_limit">erlang:system_info(port_limit)</seealso>.</p> + <p>The default value used is normally <c>65536</c>. However, if + the runtime system is able to determine maximum amount of file + descriptors that it is allowed to open and this value is larger + than <c>65536</c>, the chosen value will increased to a value + larger or equal to the maximum amount of file descriptors that + can be opened.</p> + <p>Previously the environment variable <c>ERL_MAX_PORTS</c> was used + for setting the maximum number of simultaneously existing ports. This + environment variable is deprecated, and scheduled for removal in + OTP-R17, but can still be used.</p> </item> <tag><marker id="compat_rel"><c><![CDATA[+R ReleaseNumber]]></c></marker></tag> <item> @@ -601,21 +639,14 @@ default. This flags sets the emulator in compatibility mode with an earlier Erlang/OTP release <c><![CDATA[ReleaseNumber]]></c>. The release number must be in the range - <c><![CDATA[7..<current release>]]></c>. This limits the emulator, - making it possible for it to communicate with Erlang nodes - (as well as C- and Java nodes) running that earlier release.</p> - <p>For example, an R10 node is not automatically compatible - with an R9 node, but R10 nodes started with the <c><![CDATA[+R 9]]></c> - flag can co-exist with R9 nodes in the same distributed - Erlang system, they are R9-compatible.</p> + <c><![CDATA[<current release>-2..<current release>]]></c>. This + limits the emulator, making it possible for it to communicate + with Erlang nodes (as well as C- and Java nodes) running that + earlier release.</p> <p>Note: Make sure all nodes (Erlang-, C-, and Java nodes) of a distributed Erlang system is of the same Erlang/OTP release, or from two different Erlang/OTP releases X and Y, where <em>all</em> Y nodes have compatibility mode X.</p> - <p>For example: A distributed Erlang system can consist of - R10 nodes, or of R9 nodes and R9-compatible R10 nodes, but - not of R9 nodes, R9-compatible R10 nodes and "regular" R10 - nodes, as R9 and "regular" R10 nodes are not compatible.</p> </item> <tag><c><![CDATA[+r]]></c></tag> <item> @@ -1026,7 +1057,7 @@ the given number of seconds have elapsed, the emulator will be terminated by a SIGALRM signal.</p> </item> - <tag><c><![CDATA[ERL_AFLAGS]]></c></tag> + <tag><marker id="ERL_AFLAGS"><c><![CDATA[ERL_AFLAGS]]></c></marker></tag> <item> <p>The content of this environment variable will be added to the beginning of the command line for <c><![CDATA[erl]]></c>.</p> @@ -1036,7 +1067,7 @@ the <c><![CDATA[-extra]]></c> section, i.e. the end of the command line following after an <c><![CDATA[-extra]]></c> flag.</p> </item> - <tag><c><![CDATA[ERL_ZFLAGS]]></c> and <c><![CDATA[ERL_FLAGS]]></c></tag> + <tag><marker id="ERL_ZFLAGS"><c><![CDATA[ERL_ZFLAGS]]></c></marker> and <marker id="ERL_FLAGS"><c><![CDATA[ERL_FLAGS]]></c></marker></tag> <item> <p>The content of these environment variables will be added to the end of the command line for <c><![CDATA[erl]]></c>.</p> diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index 0963904b83..2da456d49f 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -3225,10 +3225,11 @@ os_prompt% </pre> the owning process using signals of the form <c>{'EXIT', Port, PosixCode}</c>. See <c>file(3)</c> for possible values of <c>PosixCode</c>.</p> - <p><marker id="ERL_MAX_PORTS"></marker> - The maximum number of ports that can be open at the same - time is 1024 by default, but can be configured by - the environment variable <c>ERL_MAX_PORTS</c>.</p> + <p>The maximum number of ports that can be open at the same + time can be configured by passing the + <seealso marker="erl#max_ports"><c>+Q</c></seealso> + command line flag to + <seealso marker="erl"><c>erl(1)</c></seealso>.</p> </desc> </func> <func> @@ -5955,17 +5956,33 @@ ok </item> <tag><c>process_count</c></tag> <item> + <p>Returns the number of ports currently existing at + the local node as an integer. The same value as + <c>length(erlang:ports())</c> returns.</p> + </item> + <tag><marker id="system_info_port_limit"><c>port_limit</c></marker></tag> + <item> + <p>Returns the maximum number of simultaneously existing + ports at the local node as an integer. This limit + can be configured at startup by using the + <seealso marker="erl#max_ports"><c>+Q</c></seealso> + command line flag of + <seealso marker="erl"><c>erl(1)</c></seealso>.</p> + </item> + <tag><c>process_count</c></tag> + <item> <p>Returns the number of processes currently existing at the local node as an integer. The same value as <c>length(processes())</c> returns.</p> </item> - <tag><c>process_limit</c></tag> + <tag><marker id="system_info_process_limit"><c>process_limit</c></marker></tag> <item> - <p>Returns the maximum number of concurrently existing + <p>Returns the maximum number of simultaneously existing processes at the local node as an integer. This limit - can be configured at startup by using the command line - flag <c>+P</c>, see - <seealso marker="erts:erl#max_processes">erl(1)</seealso>.</p> + can be configured at startup by using the + <seealso marker="erl#max_processes"><c>+P</c></seealso> + command line flag of + <seealso marker="erl"><c>erl(1)</c></seealso>.</p> </item> <tag><c>procs</c></tag> <item> |