diff options
Diffstat (limited to 'erts/doc/src/erl.xml')
| -rw-r--r-- | erts/doc/src/erl.xml | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index df80142ce1..f477280a6f 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -603,6 +603,24 @@ <item> <p>Force ets memory block to be moved on realloc.</p> </item> + <tag><marker id="+rg"><c><![CDATA[+rg ReaderGroupsLimit]]></c></marker></tag> + <item> + <p>Limits the amount of reader groups used by read/write locks + optimized for read operations in the Erlang runtime system. By + default the reader groups limit equals 8.</p> + <p>When the amount of schedulers is less than or equal to the reader + groups limit, each scheduler has its own reader group. When the + amount of schedulers is larger than the reader groups limit, + schedulers share reader groups. Shared reader groups degrades + read lock and read unlock performance while a large amount of + reader groups degrades write lock performance, so the limit is a + tradeoff between performance for read operations and performance + for write operations. Each reader group currently consumes 64 byte + in each read/write lock. Also note that a runtime system using + shared reader groups benefits from <seealso marker="#+sbt">binding + schedulers to logical processors</seealso>, since the reader groups + are distributed better between schedulers.</p> + </item> <tag><marker id="+S"><c><![CDATA[+S Schedulers:SchedulerOnline]]></c></marker></tag> <item> <p>Sets the amount of scheduler threads to create and scheduler @@ -667,8 +685,8 @@ <seealso marker="erlang#system_flag_scheduler_bind_type">erlang:system_flag(scheduler_bind_type, default_bind)</seealso>. </p></item> </taglist> - <p>Binding of schedulers are currently only supported on newer - Linux and Solaris systems.</p> + <p>Binding of schedulers is currently only supported on newer + Linux, Solaris, and Windows systems.</p> <p>If no CPU topology is available when the <c>+sbt</c> flag is processed and <c>BindType</c> is any other type than <c>u</c>, the runtime system will fail to start. CPU |