diff options
Diffstat (limited to 'erts/doc')
-rw-r--r-- | erts/doc/src/erl.xml | 42 | ||||
-rw-r--r-- | erts/doc/src/erlang.xml | 51 | ||||
-rw-r--r-- | erts/doc/src/notes.xml | 136 |
3 files changed, 163 insertions, 66 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index 638e88ca31..71fe08d4e6 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -538,20 +538,6 @@ <p>Note that a distributed node will fail to start if epmd is not running.</p> </item> - <tag><marker id="smp"/><c><![CDATA[-smp [enable|auto|disable]]]></c></tag> - <item> - <p><c>-smp enable</c> and <c>-smp</c> start the Erlang runtime - system with SMP support enabled. This can fail if no runtime - system with SMP support is available. <c>-smp auto</c> starts - the Erlang runtime system with SMP support enabled if it is - available and more than one logical processor is detected. - <c>-smp disable</c> starts a runtime system without SMP support. - The runtime system without SMP support is deprecated and will - be removed in a future major release.</p> - <note> - <p>See also flag<seealso marker="#+S"><c>+S</c></seealso>.</p> - </note> - </item> <tag><c><![CDATA[-version]]></c> (emulator flag)</tag> <item> <p>Makes the emulator print its version number. The same @@ -902,7 +888,7 @@ <c><![CDATA[+S Schedulers:SchedulerOnline]]></c></tag> <item> <p>Sets the number of scheduler threads to create and scheduler threads - to set online when SMP support has been enabled. The maximum for both + to set online. The maximum for both values is 1024. If the Erlang runtime system is able to determine the number of logical processors configured and logical processors available, <c>Schedulers</c> defaults to logical processors @@ -920,8 +906,6 @@ <p>Specifying value <c>0</c> for <c>Schedulers</c> or <c>SchedulersOnline</c> resets the number of scheduler threads or scheduler threads online, respectively, to its default value.</p> - <p>This option is ignored if the emulator does not have SMP support - enabled (see flag <seealso marker="#smp"><c>-smp</c></seealso>).</p> </item> <tag><marker id="+SP"/><c><![CDATA[+SP SchedulersPercentage:SchedulersOnlinePercentage]]></c></tag> @@ -929,8 +913,8 @@ <p>Similar to <seealso marker="#+S"><c>+S</c></seealso> but uses percentages to set the number of scheduler threads to create, based on logical processors configured, and scheduler threads to set online, - based on logical processors available, when SMP support has been - enabled. Specified values must be > 0. For example, + based on logical processors available. + Specified values must be > 0. For example, <c>+SP 50:25</c> sets the number of scheduler threads to 50% of the logical processors configured, and the number of scheduler threads online to 25% of the logical processors available. @@ -945,15 +929,13 @@ and 8 logical cores available, the combination of the options <c>+S 4:4 +SP 50:25</c> (in either order) results in 2 scheduler threads (50% of 4) and 1 scheduler thread online (25% of 4).</p> - <p>This option is ignored if the emulator does not have SMP support - enabled (see flag <seealso marker="#smp"><c>-smp</c></seealso>).</p> </item> <tag><marker id="+SDcpu"/><c><![CDATA[+SDcpu DirtyCPUSchedulers:DirtyCPUSchedulersOnline]]></c></tag> <item> <p>Sets the number of dirty CPU scheduler threads to create and dirty - CPU scheduler threads to set online when threading support has been - enabled. The maximum for both values is 1024, and each value is + CPU scheduler threads to set online. + The maximum for both values is 1024, and each value is further limited by the settings for normal schedulers:</p> <list type="bulleted"> <item>The number of dirty CPU scheduler threads created cannot exceed @@ -977,16 +959,14 @@ executing on ordinary schedulers. If the amount of dirty CPU 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.</p> </item> <tag><marker id="+SDPcpu"/><c><![CDATA[+SDPcpu DirtyCPUSchedulersPercentage:DirtyCPUSchedulersOnlinePercentage]]></c></tag> <item> <p>Similar to <seealso marker="#+SDcpu"><c>+SDcpu</c></seealso> but uses percentages to set the number of dirty CPU scheduler threads to - create and the number of dirty CPU scheduler threads to set online - when threading support has been enabled. Specified values must be + create and the number of dirty CPU scheduler threads to set online. + Specified values must be > 0. For example, <c>+SDPcpu 50:25</c> sets the number of dirty CPU scheduler threads to 50% of the logical processors configured and the number of dirty CPU scheduler threads online to 25% of the @@ -1003,13 +983,11 @@ the combination of the options <c>+SDcpu 4:4 +SDPcpu 50:25</c> (in 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.</p> </item> <tag><marker id="+SDio"/><c><![CDATA[+SDio DirtyIOSchedulers]]></c></tag> <item> - <p>Sets the number of dirty I/O scheduler threads to create when - threading support has been enabled. Valid range is 0-1024. By + <p>Sets the number of dirty I/O scheduler threads to create. + Valid range is 0-1024. By default, the number of dirty I/O scheduler threads created is 10, same as the default number of threads in the <seealso marker="#async_thread_pool_size">async thread pool</seealso>.</p> @@ -1019,8 +997,6 @@ expected to execute on dirty I/O schedulers. If the user should schedule CPU 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.</p> </item> <tag><c><![CDATA[+sFlag Value]]></c></tag> <item> diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index f1fcbd7532..797b36bf13 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -2086,23 +2086,26 @@ os_prompt%</pre> <item>The runtime system exits with integer value <c><anno>Status</anno></c> as status code to the calling environment (OS). + <note> + <p>On many platforms, the OS supports only status + codes 0-255. A too large status code is truncated by clearing + the high bits.</p> + </note> </item> <tag>string()</tag> <item>An Erlang crash dump is produced with <c><anno>Status</anno></c> as slogan. Then the runtime system exits with status code <c>1</c>. - Note that only code points in the range 0-255 may be used - and the string will be truncated if longer than 200 characters. + The string will be truncated if longer than 200 characters. + <note> + <p>Before ERTS 9.1 (OTP-20.1) only code points in the range 0-255 + was accepted in the string. Now any unicode string is valid.</p> + </note> </item> <tag><c>abort</c></tag> <item>The runtime system aborts producing a core dump, if that is enabled in the OS. </item> </taglist> - <note> - <p>On many platforms, the OS supports only status - codes 0-255. A too large status code is truncated by clearing - the high bits.</p> - </note> <p>For integer <c><anno>Status</anno></c>, the Erlang runtime system closes all ports and allows async threads to finish their operations before exiting. To exit without such flushing, use @@ -4427,7 +4430,6 @@ RealSystem = system + MissedSystem</code> <desc> <p><c><anno>Locking</anno></c> is one of the following:</p> <list type="bulleted"> - <item><c>false</c> (emulator without SMP support)</item> <item><c>port_level</c> (port-specific locking)</item> <item><c>driver_level</c> (driver-specific locking)</item> </list> @@ -4831,8 +4833,8 @@ RealSystem = system + MissedSystem</code> selected for execution. Notice however that this does <em>not</em> mean that no processes on priority <c>low</c> or <c>normal</c> can run when processes - are running on priority <c>high</c>. On the runtime - system with SMP support, more processes can be running + are running on priority <c>high</c>. When using multiple + schedulers, more processes can be running in parallel than processes on priority <c>high</c>. That is, a <c>low</c> and a <c>high</c> priority process can execute at the same time.</p> @@ -4847,10 +4849,8 @@ RealSystem = system + MissedSystem</code> execution.</p> <note> <p>Do not depend on the scheduling - to remain exactly as it is today. Scheduling, at least on - the runtime system with SMP support, is likely to be - changed in a future release to use available - processor cores better.</p> + to remain exactly as it is today. Scheduling is likely to be + changed in a future release to use available processor cores better.</p> </note> <p>There is <em>no</em> automatic mechanism for avoiding priority inversion, such as priority inheritance @@ -6362,8 +6362,7 @@ true</pre> <p><c>statistics(exact_reductions)</c> is a more expensive operation than <seealso marker="#statistics_reductions"> - statistics(reductions)</seealso>, - especially on an Erlang machine with SMP support.</p> + statistics(reductions)</seealso>.</p> </note> </desc> </func> @@ -6747,8 +6746,8 @@ ok 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> + 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 @@ -8118,9 +8117,7 @@ ok <taglist> <tag><c>disabled</c></tag> <item> - <p>The emulator has only one scheduler thread. The - emulator does not have SMP support, or have been - started with only one scheduler thread.</p> + <p>The emulator has been started with only one scheduler thread.</p> </item> <tag><c>blocked</c></tag> <item> @@ -8483,8 +8480,7 @@ ok </item> <tag><c>smp_support</c></tag> <item> - <p>Returns <c>true</c> if the emulator has been compiled - with SMP support, otherwise <c>false</c> is returned.</p> + <p>Returns <c>true</c>.</p> </item> <tag><marker id="system_info_start_time"/><c>start_time</c></tag> <item> @@ -8507,8 +8503,7 @@ ok </item> <tag><c>threads</c></tag> <item> - <p>Returns <c>true</c> if the emulator has been compiled - with thread support, otherwise <c>false</c> is returned.</p> + <p>Returns <c>true</c>.</p> </item> <tag><c>thread_pool_size</c></tag> <item> @@ -10627,9 +10622,9 @@ true</pre> <c>receive after 1 -> ok end</c>, except that <c>yield()</c> is faster.</p> <warning> - <p>There is seldom or never any need to use this BIF, - especially in the SMP emulator, as other processes have a - chance to run in another scheduler thread anyway. + <p>There is seldom or never any need to use this BIF + as other processes have a chance to run in another scheduler + thread anyway. Using this BIF without a thorough grasp of how the scheduler works can cause performance degradation.</p> </warning> diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml index 7003564f95..76aab90e9d 100644 --- a/erts/doc/src/notes.xml +++ b/erts/doc/src/notes.xml @@ -31,6 +31,88 @@ </header> <p>This document describes the changes made to the ERTS application.</p> +<section><title>Erts 9.0.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A timer internal bit-field used for storing scheduler id + was too small. As a result, VM internal timer data + structures could become inconsistent when using 1024 + schedulers on the system. Note that systems with less + than 1024 schedulers are not effected by this bug.</p> + <p> + This bug was introduced in ERTS version 7.0 (OTP 18.0).</p> + <p> + Own Id: OTP-14548 Aux Id: OTP-11997, ERL-468 </p> + </item> + <item> + <p> + Automatic cleanup of a BIF timer, when the owner process + terminated, could race with the timeout of the timer. + This could cause the VM internal data structures to + become inconsistent which very likely caused a VM crash.</p> + <p> + This bug was introduced in ERTS version 9.0 (OTP 20.0).</p> + <p> + Own Id: OTP-14554 Aux Id: OTP-14356, ERL-468 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 9.0.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>Binary append operations did not check for overflow, + resulting in nonsensical results when huge binaries were + appended.</p> + <p> + Own Id: OTP-14524</p> + </item> + </list> + </section> + +</section> + +<section><title>Erts 9.0.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Added missing release notes for OTP-14491 ("performance + bug in pre-allocators") which was included in erts-9.0.1 + (OTP-20.0.1).</p> + <p> + Own Id: OTP-14494</p> + </item> + <item> + <p>Fixed a bug that prevented TCP sockets from being + closed properly on send timeouts.</p> + <p> + Own Id: OTP-14509</p> + </item> + <item> + <p> + Fixed bug in operator <c>bxor</c> causing erroneuos + result when one operand is a big <em>negative</em> + integer with the lowest <c>N*W</c> bits as zero and the + other operand not larger than <c>N*W</c> bits. <c>N</c> + is an integer of 1 or larger and <c>W</c> is 32 or 64 + depending on word size.</p> + <p> + Own Id: OTP-14514</p> + </item> + </list> + </section> + +</section> + <section><title>Erts 9.0.1</title> <section><title>Fixed Bugs and Malfunctions</title> @@ -63,13 +145,23 @@ <p> Own Id: OTP-14484</p> </item> + <item> + <p> + Fix performance bug in pre-allocators that could cause + them to permanently fall back on normal more expensive memory + allocation. Pre-allocators are used for quick allocation + of short lived meta data used by messages and other + scheduled tasks. Bug exists since OTP_R15B02. + [this release note was missing in erts-9.0.1]</p> + <p> + Own Id: OTP-14491</p> + </item> </list> </section> </section> <section><title>Erts 9.0</title> - <section><title>Fixed Bugs and Malfunctions</title> <list> <item> @@ -668,6 +760,42 @@ </section> +<section><title>Erts 8.3.5.1</title> + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed a bug in gen_tcp:send where it never returned when + repeatedly called on a remotely closed TCP socket.</p> + <p> + Own Id: OTP-13939 Aux Id: ERL-193 </p> + </item> + <item> + <p> + Fixed segfault that could happen during cleanup of + aborted erlang:port_command/3 calls. A port_command is + aborted if the port is closed at the same time as the + port_command was issued. This bug was introduced in + erts-8.0.</p> + <p> + Own Id: OTP-14481</p> + </item> + <item> + <p> + Fixed implementation of <c>statistics(wall_clock)</c> and + <c>statistics(runtime)</c> so that values do not + unnecessarily wrap due to the emulator. Note that the + values returned by <c>statistics(runtime)</c> may still + wrap due to limitations in the underlying functionality + provided by the operating system.</p> + <p> + Own Id: OTP-14484</p> + </item> + </list> + </section> + +</section> + <section><title>Erts 8.3.5</title> <section><title>Fixed Bugs and Malfunctions</title> @@ -3413,8 +3541,7 @@ <p>The previously introduced "eager check I/O" feature is now enabled by default.</p> <p>Eager check I/O can be disabled using the <c>erl</c> - command line argument: <seealso - marker="erl#+secio"><c>+secio false</c></seealso></p> + command line argument: <c>+secio false</c></p> <p>Characteristics impact compared to previous default:</p> <list> <item>Lower latency and smoother management of externally triggered I/O operations.</item> @@ -4195,8 +4322,7 @@ prioritized to the same extent as when eager check I/O is disabled.</p> <p>Eager check I/O can be enabled using the <c>erl</c> - command line argument: <seealso - marker="erl#+secio"><c>+secio true</c></seealso></p> + command line argument: <c>+secio true</c></p> <p>Characteristics impact when enabled:</p> <list> <item>Lower latency and smoother management of externally triggered I/O operations.</item> <item>A slightly reduced |