diff options
Diffstat (limited to 'erts/doc/src')
| -rw-r--r-- | erts/doc/src/absform.xml | 2 | ||||
| -rw-r--r-- | erts/doc/src/erl.xml | 12 | ||||
| -rw-r--r-- | erts/doc/src/erl_ext_dist.xml | 15 | ||||
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 112 | ||||
| -rw-r--r-- | erts/doc/src/erl_tracer.xml | 2 | ||||
| -rw-r--r-- | erts/doc/src/erlang.xml | 283 | ||||
| -rw-r--r-- | erts/doc/src/zlib.xml | 12 |
7 files changed, 239 insertions, 199 deletions
diff --git a/erts/doc/src/absform.xml b/erts/doc/src/absform.xml index ab00d47425..fe8e3b30e7 100644 --- a/erts/doc/src/absform.xml +++ b/erts/doc/src/absform.xml @@ -886,7 +886,7 @@ Rep(Fc) = <c>[Rep(C_1), ..., Rep(C_k)]</c>.</p> <list type="bulleted"> - <item>If C is a constraint <c>is_subtype(V, T)</c> or <c>V :: T</c>, + <item>If C is a constraint <c>V :: T</c>, where <c>V</c> is a type variable and <c>T</c> is a type, then Rep(C) = <c>{type,LINE,constraint,[{atom,LINE,is_subtype},[Rep(V),Rep(T)]]}</c>. diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index 8da832ac37..4e32118405 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -946,9 +946,7 @@ schedulers was allowed to be unlimited, dirty CPU bound jobs would potentially starve normal jobs.</p> <p>This option is ignored if the emulator does not have threading - support enabled. <em>This option is experimental</em> and - is supported only if the emulator was configured and built with - support for dirty schedulers enabled (it is disabled by default).</p> + support enabled.</p> </item> <tag><marker id="+SDPcpu"/><c><![CDATA[+SDPcpu DirtyCPUSchedulersPercentage:DirtyCPUSchedulersOnlinePercentage]]></c></tag> @@ -974,9 +972,7 @@ either order) results in 2 dirty CPU scheduler threads (50% of 4) and 1 dirty CPU scheduler thread online (25% of 4).</p> <p>This option is ignored if the emulator does not have threading - support enabled. <em>This option is experimental</em> and - is supported only if the emulator was configured and built with - support for dirty schedulers enabled (it is disabled by default).</p> + support enabled.</p> </item> <tag><marker id="+SDio"/><c><![CDATA[+SDio DirtyIOSchedulers]]></c></tag> <item> @@ -992,9 +988,7 @@ bound jobs on dirty I/O schedulers, these jobs might starve ordinary jobs executing on ordinary schedulers.</p> <p>This option is ignored if the emulator does not have threading - support enabled. <em>This option is experimental</em> and - is supported only if the emulator was configured and built with - support for dirty schedulers enabled (it is disabled by default).</p> + support enabled.</p> </item> <tag><c><![CDATA[+sFlag Value]]></c></tag> <item> diff --git a/erts/doc/src/erl_ext_dist.xml b/erts/doc/src/erl_ext_dist.xml index 4f799f8f34..a436a9ca74 100644 --- a/erts/doc/src/erl_ext_dist.xml +++ b/erts/doc/src/erl_ext_dist.xml @@ -119,16 +119,11 @@ <tcaption>Compressed Data Format when Expanded</tcaption></table> <marker id="utf8_atoms"/> <note> - <p>As from ERTS 5.10 (OTP R16) support - for UTF-8 encoded atoms has been introduced in the external format. - However, only characters that can be encoded using Latin-1 (ISO-8859-1) - are currently supported in atoms. The support for UTF-8 encoded atoms - in the external format has been implemented to be able to support - all Unicode characters in atoms in <em>some future release</em>. - Until full Unicode support for atoms has been introduced, - it is an <em>error</em> to pass atoms containing - characters that cannot be encoded in Latin-1, and <em>the behavior is - undefined</em>.</p> + <p>As from ERTS 9.0 (OTP 20), UTF-8 encoded atoms may contain any Unicode + character. Although the support for UTF-8 encoded atoms in the external + format is available since ERTS 5.10 (OTP R16), passing atoms that cannot + be encoded in Latin-1 is an <em>error</em> in versions earlier than + Erlang/OTP 20, and <em>the behavior is undefined</em>.</p> <p>When distribution flag <seealso marker="erl_dist_protocol#dflags"> <c>DFLAG_UTF8_ATOMS</c></seealso> has been exchanged between both nodes in the <seealso marker="erl_dist_protocol#distribution_handshake"> diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index b5dc9037c4..74a551d60b 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -80,7 +80,7 @@ <code type="none"> /* niftest.c */ -#include "erl_nif.h" +#include <erl_nif.h> static ERL_NIF_TERM hello(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) { @@ -123,7 +123,7 @@ ok "Hello world!"</code> <p>A better solution for a real module is to take advantage of the new - directive <c>on load</c> (see section + directive <c>on_load</c> (see section <seealso marker="doc/reference_manual:code_loading#on_load">Running a Function When a Module is Loaded</seealso> in the Erlang Reference Manual) to load the NIF library automatically when the module is @@ -135,27 +135,14 @@ ok away by the compiler, causing loading of the NIF library to fail.</p> </note> - <p>A loaded NIF library is tied to the Erlang module code version - that loaded it. If the module is upgraded with a new version, the - new Erlang code need to load its own NIF library (or maybe choose not - to). The new code version can, however, choose to load the - same NIF library as the old code if it wants to. Sharing the - dynamic library means that static data defined by the library - is shared as well. To avoid unintentionally shared static - data, each Erlang module code can keep its own private data. This - private data can be set when the NIF library is loaded and - then retrieved by calling <seealso marker="#enif_priv_data"> - <c>enif_priv_data</c></seealso>.</p> - - <p>A NIF library cannot be loaded explicitly. A library is - automatically unloaded when the module code that it belongs to is purged - by the code server.</p> + <p>Once loaded, a NIF library is persistent. It will not be unloaded + until the module code version that it belongs to is purged.</p> </description> <section> <title>Functionality</title> - <p>All functions that a NIF library needs to do with Erlang are - performed through the NIF API functions. Functions exist + <p>All interaction between NIF code and the Erlang runtime system is + performed by calling NIF API functions. Functions exist for the following functionality:</p> <taglist> @@ -286,6 +273,19 @@ return term;</code> library is postponed as long as there exist resource objects with a destructor function in the library.</p> </item> + <tag>Module upgrade and static data</tag> + <item> + <p>A loaded NIF library is tied to the Erlang module instance + that loaded it. If the module is upgraded, the new module instance + needs to load its own NIF library (or maybe choose not to). The new + module instance can, however, choose to load the exact same NIF library + as the old code if it wants to. Sharing the dynamic library means that + static data defined by the library is shared as well. To avoid + unintentionally shared static data between module instances, each Erlang + module version can keep its own private data. This private data can be + set when the NIF library is loaded and later retrieved by calling + <seealso marker="#enif_priv_data"><c>enif_priv_data</c></seealso>.</p> + </item> <tag>Threads and concurrency</tag> <item> <p>A NIF is thread-safe without any explicit synchronization as @@ -296,8 +296,8 @@ return term;</code> synchronization. This includes terms in process-independent environments that are shared between threads. Resource objects also require synchronization if you treat them as mutable.</p> - <p>The library initialization callbacks <c>load</c>, <c>reload</c>, and - <c>upgrade</c> are all thread-safe even for shared state data.</p> + <p>The library initialization callbacks <c>load</c> and + <c>upgrade</c> are thread-safe even for shared state data.</p> </item> <tag><marker id="version_management"/>Version Management</tag> <item> @@ -402,14 +402,14 @@ return term;</code> <tag><marker id="dirty_nifs"/>Dirty NIF</tag> <item> <note> - <p><em>The dirty NIF functionality described here - is experimental</em>. Dirty NIF support is available only when - the emulator is configured with dirty schedulers enabled. This - feature is disabled by default. The Erlang runtime - without SMP support does not support dirty schedulers even when - the dirty scheduler support is enabled. To check at runtime for - the presence of dirty scheduler threads, code can use the - <seealso marker="#enif_system_info"> + <p>Dirty NIF support is available only when the emulator is + configured with dirty scheduler support. As of ERTS version + 9.0, dirty scheduler support is enabled by default on the + runtime system with SMP support. The Erlang runtime without + SMP support does <em>not</em> support dirty schedulers even + when the dirty scheduler support is explicitly enabled. To + check at runtime for the presence of dirty scheduler threads, + code can use the <seealso marker="#enif_system_info"> <c>enif_system_info()</c></seealso> API function.</p> </note> <p>A NIF that cannot be split and cannot execute in a millisecond @@ -498,7 +498,7 @@ return term;</code> <title>Initialization</title> <taglist> <tag><marker id="ERL_NIF_INIT"/><c>ERL_NIF_INIT(MODULE, - ErlNifFunc funcs[], load, reload, upgrade, unload)</c></tag> + ErlNifFunc funcs[], load, NULL, upgrade, unload)</c></tag> <item> <p>This is the magic macro to initialize a NIF library. It is to be evaluated in global file scope.</p> @@ -507,11 +507,14 @@ return term;</code> the macro.</p> <p><c>funcs</c> is a static array of function descriptors for all the implemented NIFs in this library.</p> - <p><c>load</c>, <c>reload</c>, <c>upgrade</c> and <c>unload</c> - are pointers to functions. One of <c>load</c>, <c>reload</c>, or + <p><c>load</c>, <c>upgrade</c> and <c>unload</c> + are pointers to functions. One of <c>load</c> or <c>upgrade</c> is called to initialize the library. <c>unload</c> is called to release the library. All are described individually below.</p> + <p>The fourth argument <c>NULL</c> is ignored. It + was earlier used for the deprectated <c>reload</c> callback + which is no longer supported since OTP 20.</p> <p>If compiling a NIF for static inclusion through <c>--enable-static-nifs</c>, you must define <c>STATIC_ERLANG_NIF</c> before the <c>ERL_NIF_INIT</c> declaration.</p> @@ -522,7 +525,7 @@ return term;</code> <p><c>load</c> is called when the NIF library is loaded and no previously loaded library exists for this module.</p> <p><c>*priv_data</c> can be set to point to some private data - that the library needs to keep a state between NIF + if the library needs to keep a state between NIF calls. <c>enif_priv_data</c> returns this pointer. <c>*priv_data</c> is initialized to <c>NULL</c> when <c>load</c> is called.</p> @@ -539,7 +542,7 @@ return term;</code> and there is old code of this module with a loaded NIF library.</p> <p>Works as <c>load</c>, except that <c>*old_priv_data</c> already contains the value set by the last call to <c>load</c> or - <c>reload</c> for the old module code. <c>*priv_data</c> is + <c>upgrade</c> for the old module code. <c>*priv_data</c> is initialized to <c>NULL</c> when <c>upgrade</c> is called. It is allowed to write to both <c>*priv_data</c> and <c>*old_priv_data.</c></p> @@ -551,27 +554,7 @@ return term;</code> <item> <p><c>unload</c> is called when the module code that the NIF library belongs to is purged as old. New code of the same - module may or may not exist. Notice that <c>unload</c> is not - called for a replaced library as a consequence of <c>reload</c>.</p> - </item> - <tag><marker id="reload"/><c>int (*reload)(ErlNifEnv* env, void** - priv_data, ERL_NIF_TERM load_info)</c></tag> - <item> - <note> - <p><em>The reload mechanism is deprecated.</em> It was only intended - as a development feature. Do not use it as an upgrade method for - live production systems. It can be removed in future releases. - Ensure to pass <c>reload</c> as <c>NULL</c> to - <seealso marker="#ERL_NIF_INIT"><c>ERL_NIF_INIT</c></seealso> - to disable it when not used.</p> - </note> - <p><c>reload</c> is called when the NIF library is loaded and a - previously loaded library already exists for this module code.</p> - <p>Works as <c>load</c>, except that - <c>*priv_data</c> already contains the value set by the - previous call to <c>load</c> or <c>reload</c>.</p> - <p>The library fails to load if <c>reload</c> returns - anything other than <c>0</c> or if <c>reload</c> is <c>NULL</c>.</p> + module may or may not exist.</p> </item> </taglist> </section> @@ -659,9 +642,6 @@ typedef struct { <p><c>flags</c> can be used to indicate that the NIF is a <seealso marker="#dirty_nifs">dirty NIF</seealso> that is to be executed on a dirty scheduler thread.</p> - <p><em>The dirty NIF functionality described here is - experimental.</em> You have to enable support for dirty - schedulers when building OTP to try out the functionality.</p> <p>If the dirty NIF is expected to be CPU-bound, its <c>flags</c> field is to be set to <c>ERL_NIF_DIRTY_JOB_CPU_BOUND</c> or <c>ERL_NIF_DIRTY_JOB_IO_BOUND</c>.</p> @@ -2249,9 +2229,8 @@ enif_map_iterator_destroy(env, &iter);</code> returns <c>NULL</c> and sets <c>*tried</c> to <c>flags</c>. It is allowed to set <c>tried</c> to <c>NULL</c>.</p> <p>Notice that <c>enif_open_resource_type</c> is only allowed to be - called in the three callbacks - <seealso marker="#load"><c>load</c></seealso>, - <seealso marker="#reload"><c>reload</c></seealso>, and + called in the two callbacks + <seealso marker="#load"><c>load</c></seealso> and <seealso marker="#upgrade"><c>upgrade</c></seealso>.</p> </desc> </func> @@ -2305,10 +2284,8 @@ enif_map_iterator_destroy(env, &iter);</code> <fsummary>Get the private data of a NIF library.</fsummary> <desc> <p>Returns the pointer to the private data that was set by - <seealso marker="#load"><c>load</c></seealso>, - <seealso marker="#reload"><c>reload</c></seealso>, or + <seealso marker="#load"><c>load</c></seealso> or <seealso marker="#upgrade"><c>upgrade</c></seealso>.</p> - <p>Was previously named <c>enif_get_data</c>.</p> </desc> </func> @@ -2470,9 +2447,6 @@ enif_map_iterator_destroy(env, &iter);</code> application to break up long-running work into multiple regular NIF calls or to schedule a <seealso marker="#dirty_nifs"> dirty NIF</seealso> to execute on a dirty scheduler thread.</p> - <p><em>The dirty NIF functionality described here is - experimental.</em> You have to enable support for dirty - schedulers when building OTP to try out the functionality.</p> <taglist> <tag><c>fun_name</c></tag> <item> @@ -2483,13 +2457,13 @@ enif_map_iterator_destroy(env, &iter);</code> <tag><c>flags</c></tag> <item> <p>Must be set to <c>0</c> for a regular NIF. If the emulator was - built with the experimental dirty scheduler support enabled, + built with dirty scheduler support enabled, <c>flags</c> can be set to either <c>ERL_NIF_DIRTY_JOB_CPU_BOUND</c> if the job is expected to be CPU-bound, or <c>ERL_NIF_DIRTY_JOB_IO_BOUND</c> for jobs that will be I/O-bound. If dirty scheduler threads are not available in the emulator, an attempt to schedule such a job - results in a <c>badarg</c> exception.</p> + results in a <c>notsup</c> exception.</p> </item> <tag><c>argc</c> and <c>argv</c></tag> <item> diff --git a/erts/doc/src/erl_tracer.xml b/erts/doc/src/erl_tracer.xml index 83eef374ca..43613c31b1 100644 --- a/erts/doc/src/erl_tracer.xml +++ b/erts/doc/src/erl_tracer.xml @@ -684,7 +684,7 @@ trace(_, _, _, _, _) -> <p><c>erl_msg_tracer.c</c>:</p> <pre> -#include "erl_nif.h" +#include <erl_nif.h> /* NIF interface declarations */ static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info); diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index 112682d713..8d340a15f5 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -325,16 +325,11 @@ Z = erlang:adler32_combine(X,Y,iolist_size(Data2)).</code> is <c>latin1</c>, one byte exists for each character in the text representation. If <c><anno>Encoding</anno></c> is <c>utf8</c> or - <c>unicode</c>, the characters are encoded using UTF-8 - (that is, characters from 128 through 255 are - encoded in two bytes).</p> + <c>unicode</c>, the characters are encoded using UTF-8 where + characters may require multiple bytes.</p> <note> - <p><c>atom_to_binary(<anno>Atom</anno>, latin1)</c> never - fails, as the text representation of an atom can only - contain characters from 0 through 255. In a future release, - the text representation - of atoms can be allowed to contain any Unicode character and - <c>atom_to_binary(<anno>Atom</anno>, latin1)</c> then fails if the + <p>As from Erlang/OTP 20, atoms can contain any Unicode character + and <c>atom_to_binary(<anno>Atom</anno>, latin1)</c> may fail if the text representation for <c><anno>Atom</anno></c> contains a Unicode character > 255.</p> </note> @@ -402,13 +397,11 @@ Z = erlang:adler32_combine(X,Y,iolist_size(Data2)).</code> translation of bytes in the binary is done. If <c><anno>Encoding</anno></c> is <c>utf8</c> or <c>unicode</c>, the binary must contain - valid UTF-8 sequences. Only Unicode characters up - to 255 are allowed.</p> + valid UTF-8 sequences.</p> <note> - <p><c>binary_to_atom(<anno>Binary</anno>, utf8)</c> fails if - the binary contains Unicode characters > 255. - In a future release, such Unicode characters can be allowed and - <c>binary_to_atom(<anno>Binary</anno>, utf8)</c> does then not fail. + <p>As from Erlang/OTP 20, <c>binary_to_atom(<anno>Binary</anno>, utf8)</c> + is capable of encoding any Unicode character. Earlier versions would + fail if the binary contained Unicode characters > 255. For more information about Unicode support in atoms, see the <seealso marker="erl_ext_dist#utf8_atoms">note on UTF-8 encoded atoms</seealso> @@ -419,9 +412,7 @@ Z = erlang:adler32_combine(X,Y,iolist_size(Data2)).</code> > <input>binary_to_atom(<<"Erlang">>, latin1).</input> 'Erlang' > <input>binary_to_atom(<<1024/utf8>>, utf8).</input> -** exception error: bad argument - in function binary_to_atom/2 - called as binary_to_atom(<<208,128>>,utf8)</pre> +'Ѐ'</pre> </desc> </func> @@ -733,6 +724,19 @@ hello </func> <func> + <name name="ceil" arity="1"/> + <fsummary>Returns the smallest integer not less than the argument</fsummary> + <desc> + <p>Returns the smallest integer not less than + <c><anno>Number</anno></c>. + For example:</p> + <pre> +> <input>ceil(5.5).</input> +6</pre> + <p>Allowed in guard tests.</p> + </desc> + </func> + <func> <name name="check_old_code" arity="1"/> <fsummary>Check if a module has old code.</fsummary> <desc> @@ -1480,6 +1484,20 @@ true</pre> </func> <func> + <name name="floor" arity="1"/> + <fsummary>Returns the largest integer not greater than the argument</fsummary> + <desc> + <p>Returns the largest integer not greater than + <c><anno>Number</anno></c>. + For example:</p> + <pre> +> <input>floor(-10.5).</input> +-11</pre> + <p>Allowed in guard tests.</p> + </desc> + </func> + + <func> <name name="fun_info" arity="1"/> <fsummary>Information about a fun.</fsummary> <desc> @@ -1667,6 +1685,12 @@ true</pre> the form <c>{garbage_collect, <anno>RequestId</anno>, <anno>GCResult</anno>}</c>. </item> + + <tag><c>{type, 'major' | 'minor'}</c></tag> + <item>Triggers garbage collection of requested type. Default value is + <c>'major'</c>, which would trigger a fullsweep GC. + The option <c>'minor'</c> is considered a hint and may lead to + either minor or major GC run.</item> </taglist> <p>If <c><anno>Pid</anno></c> equals <c>self()</c>, and no <c>async</c> option has been passed, the garbage @@ -1922,26 +1946,6 @@ os_prompt%</pre> </func> <func> - <name name="hash" arity="2"/> - <fsummary>Hash function (deprecated).</fsummary> - <desc> - <p>Returns a hash value for <c><anno>Term</anno></c> within the range - <c>1..<anno>Range</anno></c>. The maximum range is 1..2^27-1.</p> - <warning> - <p><em>This BIF is deprecated, as the hash value can differ on - different architectures.</em> The hash values for integer - terms > 2^27 and large binaries are - poor. The BIF is retained for backward compatibility - reasons (it can have been used to hash records into a file), - but all new code is to use one of the BIFs - <seealso marker="#phash/2"><c>erlang:phash/2</c></seealso> or - <seealso marker="#phash2/1"><c>erlang:phash2/1,2</c></seealso> - instead.</p> - </warning> - </desc> - </func> - - <func> <name name="hd" arity="1"/> <fsummary>Head of a list.</fsummary> <desc> @@ -2368,10 +2372,10 @@ os_prompt%</pre> <desc> <p>Returns the atom whose text representation is <c><anno>String</anno></c>.</p> - <p><c><anno>String</anno></c> can only contain ISO-latin-1 - characters (that is, numbers < 256) as the implementation does not - allow Unicode characters equal to or above 256 in atoms. - For more information on Unicode support in atoms, see + <p>As from Erlang/OTP 20, <c><anno>String</anno></c> may contain + any Unicode character. Earlier versions allowed only ISO-latin-1 + characters as the implementation did not allow Unicode characters + above 255. For more information on Unicode support in atoms, see <seealso marker="erl_ext_dist#utf8_atoms">note on UTF-8 encoded atoms</seealso> in section "External Term Format" in the User's Guide.</p> @@ -2544,13 +2548,6 @@ os_prompt%</pre> <name name="load_nif" arity="2"/> <fsummary>Load NIF library.</fsummary> <desc> - <note> - <p>Before Erlang/OTP R14B, NIFs were an - experimental feature. Versions before Erlang/OTP R14B can - have different and possibly incompatible NIF semantics and - interfaces. For example, in Erlang/OTP R13B03 the return value on - failure was <c>{error,Reason,Text}</c>.</p> - </note> <p>Loads and links a dynamic library containing native implemented functions (NIFs) for a module. <c><anno>Path</anno></c> is a file path to the shareable object/dynamic library file minus @@ -2580,14 +2577,22 @@ os_prompt%</pre> <item>The library did not fulfill the requirements as a NIF library of the calling module. </item> - <tag><c>load | reload | upgrade</c></tag> + <tag><c>load | upgrade</c></tag> <item>The corresponding library callback was unsuccessful. </item> + <tag><c>reload</c></tag> + <item>A NIF library is already loaded for this module instance. + The previously deprecated <c>reload</c> feature was removed in OTP 20. + </item> <tag><c>old_code</c></tag> <item>The call to <c>load_nif/2</c> was made from the old code of a module that has been upgraded; this is not allowed. </item> + <tag><c>notsup</c></tag> + <item>Lack of support. Such as loading NIF library for a + HiPE compiled module. + </item> </taglist> </desc> </func> @@ -3784,9 +3789,6 @@ RealSystem = system + MissedSystem</code> <c><anno>Term</anno></c> within the range <c>1..<anno>Range</anno></c>. The maximum value for <c><anno>Range</anno></c> is 2^32.</p> - <p>This BIF can be used instead of the old deprecated BIF - <c>erlang:hash/2</c>, as it calculates better hashes for - all data types, but consider using <c>phash2/1,2</c> instead.</p> </desc> </func> @@ -3821,10 +3823,6 @@ RealSystem = system + MissedSystem</code> <desc> <p>Returns a string corresponding to the text representation of <c><anno>Pid</anno></c>.</p> - <warning> - <p>This BIF is intended for debugging and is not to be used - in application programs.</p> - </warning> </desc> </func> @@ -4397,10 +4395,6 @@ RealSystem = system + MissedSystem</code> <desc> <p>Returns a string corresponding to the text representation of the port identifier <c><anno>Port</anno></c>.</p> - <warning> - <p>This BIF is intended for debugging. It is not to be used - in application programs.</p> - </warning> </desc> </func> @@ -6381,12 +6375,17 @@ lists:map( <c><anno>TotalTime</anno></c> is the total time duration since <seealso marker="#system_flag_scheduler_wall_time"> <c>scheduler_wall_time</c></seealso> - activation. The time unit is undefined and can be subject - to change between releases, OSs, and system restarts. - <c>scheduler_wall_time</c> is only to be used to - calculate relative values for scheduler-utilization. - <c><anno>ActiveTime</anno></c> can never exceed - <c><anno>TotalTime</anno></c>.</p> + activation for the specific scheduler. Note that + activation time can differ significantly between + schedulers. Currently dirty schedulers are activated + at system start while normal schedulers are activated + some time after the <c>scheduler_wall_time</c> + functionality is enabled. The time unit is undefined + and can be subject to change between releases, OSs, + and system restarts. <c>scheduler_wall_time</c> is only + to be used to calculate relative values for scheduler + utilization. <c><anno>ActiveTime</anno></c> can never + exceed <c><anno>TotalTime</anno></c>.</p> <p>The definition of a busy scheduler is when it is not idle and is not scheduling (selecting) a process or port, that is:</p> @@ -6404,15 +6403,37 @@ lists:map( <c>scheduler_wall_time</c></seealso> is turned off.</p> <p>The list of scheduler information is unsorted and can appear in different order between calls.</p> + <p>As of ERTS version 9.0, also dirty CPU schedulers will + be included in the result. That is, all scheduler threads + that are expected to handle CPU bound work. If you also + want information about dirty I/O schedulers, use + <seealso marker="#statistics_scheduler_wall_time_all"><c>statistics(scheduler_wall_time_all)</c></seealso> + instead.</p> + + <p>Normal schedulers will have scheduler identifiers in + the range <c>1 =< <anno>SchedulerId</anno> =< + </c><seealso marker="#system_info_schedulers"><c>erlang:system_info(schedulers)</c></seealso>. + Dirty CPU schedulers will have scheduler identifiers in + the range <c>erlang:system_info(schedulers) < + <anno>SchedulerId</anno> =< erlang:system_info(schedulers) + + + </c><seealso marker="#system_info_dirty_cpu_schedulers"><c>erlang:system_info(dirty_cpu_schedulers)</c></seealso>. + </p> + <note><p>The different types of schedulers handle + specific types of jobs. Every job is assigned to a specific + scheduler type. Jobs can migrate between different schedulers + of the same type, but never between schedulers of different + types. This fact has to be taken under consideration when + evaluating the result returned.</p></note> <p>Using <c>scheduler_wall_time</c> to calculate - scheduler-utilization:</p> + scheduler utilization:</p> <pre> > <input>erlang:system_flag(scheduler_wall_time, true).</input> false > <input>Ts0 = lists:sort(erlang:statistics(scheduler_wall_time)), ok.</input> ok</pre> <p>Some time later the user takes another snapshot and calculates - scheduler-utilization per scheduler, for example:</p> + scheduler utilization per scheduler, for example:</p> <pre> > <input>Ts1 = lists:sort(erlang:statistics(scheduler_wall_time)), ok.</input> ok @@ -6427,11 +6448,32 @@ ok {7,0.973237033077876}, {8,0.9741297293248656}]</pre> <p>Using the same snapshots to calculate a total - scheduler-utilization:</p> + scheduler utilization:</p> <pre> > <input>{A, T} = lists:foldl(fun({{_, A0, T0}, {_, A1, T1}}, {Ai,Ti}) -> - {Ai + (A1 - A0), Ti + (T1 - T0)} end, {0, 0}, lists:zip(Ts0,Ts1)), A/T.</input> + {Ai + (A1 - A0), Ti + (T1 - T0)} end, {0, 0}, lists:zip(Ts0,Ts1)), + TotalSchedulerUtilization = A/T.</input> +0.9769136803764825</pre> + <p>Total scheduler utilization will equal <c>1.0</c> when + all schedulers have been active all the time between the + two measurements.</p> + <p>Another (probably more) useful value is to calculate + total scheduler utilization weighted against maximum amount + of available CPU time:</p> + <pre> +> <input>WeightedSchedulerUtilization = (TotalSchedulerUtilization + * (erlang:system_info(schedulers) + + erlang:system_info(dirty_cpu_schedulers))) + / erlang:system_info(logical_processors_available).</input> 0.9769136803764825</pre> + <p>This weighted scheduler utilization will reach <c>1.0</c> + when schedulers are active the same amount of time as + maximum available CPU time. If more schedulers exist + than available logical processors, this value may + be greater than <c>1.0</c>.</p> + <p>As of ERTS version 9.0, the Erlang runtime system + with SMP support will as default have more schedulers + than logical processors. This due to the dirty schedulers.</p> <note> <p><c>scheduler_wall_time</c> is by default disabled. To enable it, use @@ -6442,6 +6484,31 @@ ok <func> <name name="statistics" arity="1" clause_i="12"/> + <fsummary>Information about each schedulers work time.</fsummary> + <desc> + <marker id="statistics_scheduler_wall_time_all"></marker> + <p>The same as + <seealso marker="#statistics_scheduler_wall_time"><c>statistics(scheduler_wall_time)</c></seealso>, + except that it also include information about all dirty I/O + schedulers.</p> + <p>Dirty IO schedulers will have scheduler identifiers in + the range + <seealso marker="#system_info_schedulers"><c>erlang:system_info(schedulers)</c></seealso><c> + + + </c><seealso marker="#system_info_dirty_cpu_schedulers"><c>erlang:system_info(dirty_cpu_schedulers)</c></seealso><c> < + <anno>SchedulerId</anno> =< erlang:system_info(schedulers) + + erlang:system_info(dirty_cpu_schedulers) + + + </c><seealso marker="#system_info_dirty_io_schedulers"><c>erlang:system_info(dirty_io_schedulers)</c></seealso>.</p> + <note><p>Note that work executing on dirty I/O schedulers + are expected to mainly wait for I/O. That is, when you + get high scheduler utilization on dirty I/O schedulers, + CPU utilization is <em>not</em> expected to be high due to + this work.</p></note> + </desc> + </func> + <func> + <name name="statistics" arity="1" clause_i="13"/> <fsummary>Information about active processes and ports.</fsummary> <desc><marker id="statistics_total_active_tasks"></marker> <p>Returns the total amount of active processes and ports in @@ -6461,7 +6528,7 @@ ok </func> <func> - <name name="statistics" arity="1" clause_i="13"/> + <name name="statistics" arity="1" clause_i="14"/> <fsummary>Information about the run-queue lengths.</fsummary> <desc><marker id="statistics_total_run_queue_lengths"></marker> <p>Returns the total length of the run queues. That is, the number @@ -6481,7 +6548,7 @@ ok </func> <func> - <name name="statistics" arity="1" clause_i="14"/> + <name name="statistics" arity="1" clause_i="15"/> <fsummary>Information about wall clock.</fsummary> <desc> <p>Returns information about wall clock. <c>wall_clock</c> can @@ -6687,11 +6754,6 @@ ok down to 3. Similarly, the number of dirty CPU schedulers online increases proportionally to increases in the number of schedulers online.</p> - <note> - <p>The dirty schedulers functionality is experimental. - Enable support for dirty schedulers when building OTP to - try out the functionality.</p> - </note> <p>For more information, see <seealso marker="#system_info_dirty_cpu_schedulers"> <c>erlang:system_info(dirty_cpu_schedulers)</c></seealso> and @@ -7194,8 +7256,8 @@ ok </func> <func> - <name name="system_info" arity="1" clause_i="10"/> - <name name="system_info" arity="1" clause_i="11"/> + <name name="system_info" arity="1" clause_i="12"/> + <name name="system_info" arity="1" clause_i="13"/> <fsummary>Information about the CPU topology of the system.</fsummary> <type name="cpu_topology"/> <type name="level_entry"/> @@ -7295,12 +7357,12 @@ ok </func> <func> - <name name="system_info" arity="1" clause_i="27"/> - <name name="system_info" arity="1" clause_i="28"/> - <name name="system_info" arity="1" clause_i="36"/> - <name name="system_info" arity="1" clause_i="37"/> + <name name="system_info" arity="1" clause_i="29"/> + <name name="system_info" arity="1" clause_i="30"/> <name name="system_info" arity="1" clause_i="38"/> <name name="system_info" arity="1" clause_i="39"/> + <name name="system_info" arity="1" clause_i="40"/> + <name name="system_info" arity="1" clause_i="41"/> <fsummary>Information about the default process heap settings.</fsummary> <type name="message_queue_data"/> <type name="max_heap_size"/> @@ -7343,12 +7405,6 @@ ok see <seealso marker="#process_flag_max_heap_size"> <c>process_flag(max_heap_size, MaxHeapSize)</c></seealso>.</p> </item> - <tag><c>min_heap_size</c></tag> - <item> - <p>Returns <c>{min_heap_size, <anno>MinHeapSize</anno>}</c>, - where <c><anno>MinHeapSize</anno></c> is the current - system-wide minimum heap size for spawned processes.</p> - </item> <tag><marker id="system_info_message_queue_data"/> <c>message_queue_data</c></tag> <item> @@ -7361,6 +7417,12 @@ ok <seealso marker="#process_flag_message_queue_data"> <c>process_flag(message_queue_data, MQD)</c></seealso>.</p> </item> + <tag><c>min_heap_size</c></tag> + <item> + <p>Returns <c>{min_heap_size, <anno>MinHeapSize</anno>}</c>, + where <c><anno>MinHeapSize</anno></c> is the current + system-wide minimum heap size for spawned processes.</p> + </item> <tag><c>min_bin_vheap_size</c></tag> <item> <p>Returns <c>{min_bin_vheap_size, @@ -7377,8 +7439,8 @@ ok <name name="system_info" arity="1" clause_i="7"/> <name name="system_info" arity="1" clause_i="8"/> <name name="system_info" arity="1" clause_i="9"/> - <name name="system_info" arity="1" clause_i="12"/> - <name name="system_info" arity="1" clause_i="13"/> + <name name="system_info" arity="1" clause_i="10"/> + <name name="system_info" arity="1" clause_i="11"/> <name name="system_info" arity="1" clause_i="14"/> <name name="system_info" arity="1" clause_i="15"/> <name name="system_info" arity="1" clause_i="16"/> @@ -7392,15 +7454,15 @@ ok <name name="system_info" arity="1" clause_i="24"/> <name name="system_info" arity="1" clause_i="25"/> <name name="system_info" arity="1" clause_i="26"/> - <name name="system_info" arity="1" clause_i="29"/> - <name name="system_info" arity="1" clause_i="30"/> + <name name="system_info" arity="1" clause_i="27"/> + <name name="system_info" arity="1" clause_i="28"/> <name name="system_info" arity="1" clause_i="31"/> <name name="system_info" arity="1" clause_i="32"/> <name name="system_info" arity="1" clause_i="33"/> <name name="system_info" arity="1" clause_i="34"/> <name name="system_info" arity="1" clause_i="35"/> - <name name="system_info" arity="1" clause_i="40"/> - <name name="system_info" arity="1" clause_i="41"/> + <name name="system_info" arity="1" clause_i="36"/> + <name name="system_info" arity="1" clause_i="37"/> <name name="system_info" arity="1" clause_i="42"/> <name name="system_info" arity="1" clause_i="43"/> <name name="system_info" arity="1" clause_i="44"/> @@ -7429,16 +7491,28 @@ ok <name name="system_info" arity="1" clause_i="67"/> <name name="system_info" arity="1" clause_i="68"/> <name name="system_info" arity="1" clause_i="69"/> + <name name="system_info" arity="1" clause_i="70"/> + <name name="system_info" arity="1" clause_i="71"/> <fsummary>Information about the system.</fsummary> <desc> <p>Returns various information about the current system (emulator) as specified by <c><anno>Item</anno></c>:</p> <taglist> - <tag><c>allocated_areas</c>, <c>allocator</c>, - <c>alloc_util_allocators</c>, <c>allocator_sizes</c></tag> + <tag><c>atom_count</c></tag> + <item> + <marker id="system_info_atom_count"></marker> + <p>Returns the number of atoms currently existing at the + local node. The value is given as an integer.</p> + </item> + <tag><c>atom_limit</c></tag> <item> - <p>See <seealso marker="#system_info_allocator_tags"> - above</seealso>.</p> + <marker id="system_info_atom_limit"></marker> + <p>Returns the maximum number of atoms allowed. + This limit can be increased at startup by passing + command-line flag + <seealso marker="erts:erl#+t"><c>+t</c></seealso> to + <c>erl(1)</c>. + </p> </item> <tag><c>build_type</c></tag> <item> @@ -7524,9 +7598,6 @@ ok <seealso marker="erts:erl#+SDcpu"><c>+SDcpu</c></seealso> or <seealso marker="erts:erl#+SDPcpu"><c>+SDPcpu</c></seealso> in <c>erl(1)</c>.</p> - <p>Notice that the dirty schedulers functionality is - experimental. Enable support for dirty schedulers when - building OTP to try out the functionality.</p> <p>See also <seealso marker="#system_flag_dirty_cpu_schedulers_online"> <c>erlang:system_flag(dirty_cpu_schedulers_online, @@ -7556,9 +7627,6 @@ ok startup by passing command-line flag <seealso marker="erts:erl#+SDcpu"><c>+SDcpu</c></seealso> in <c>erl(1)</c>.</p> - <p>Notice that the dirty schedulers functionality is - experimental. Enable support for dirty schedulers when - building OTP to try out the functionality.</p> <p>For more information, see <seealso marker="#system_info_dirty_cpu_schedulers"> <c>erlang:system_info(dirty_cpu_schedulers)</c></seealso>, @@ -7580,9 +7648,6 @@ ok <p>This value can be set at startup by passing command-line argument <seealso marker="erts:erl#+SDio"><c>+SDio</c></seealso> in <c>erl(1)</c>.</p> - <p>Notice that the dirty schedulers functionality is - experimental. Enable support for dirty schedulers when - building OTP to try out the functionality.</p> <p>For more information, see <seealso marker="#system_info_dirty_cpu_schedulers"> <c>erlang:system_info(dirty_cpu_schedulers)</c></seealso>, diff --git a/erts/doc/src/zlib.xml b/erts/doc/src/zlib.xml index 138414a880..e1924fffee 100644 --- a/erts/doc/src/zlib.xml +++ b/erts/doc/src/zlib.xml @@ -576,6 +576,18 @@ unpack(Z, Compressed, Dict) -> </func> <func> + <name name="inflateGetDictionary" arity="1"/> + <fsummary>Return the decompression dictionary.</fsummary> + <desc> + <p>Returns the decompression dictionary currently in use + by the stream. This function must be called between + <seealso marker="#inflateInit/1"><c>inflateInit/1,2</c></seealso> + and <seealso marker="#inflateEnd/1"><c>inflateEnd</c></seealso>.</p> + <p>Only supported if ERTS was compiled with zlib >= 1.2.8.</p> + </desc> + </func> + + <func> <name name="open" arity="0"/> <fsummary>Open a stream and return a stream reference.</fsummary> <desc> |