<!--
  Copyright (C) Igor Sysoev
  Copyright (C) Nginx, Inc.
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<!DOCTYPE article SYSTEM "../../../dtd/article.dtd">

<article name="Connection processing methods"
         link="/en/docs/events.html"
         lang="en"
         rev="6">

<section>

<para>
nginx supports a variety of connection processing methods.
The availability of a particular method depends on the platform used.
On platforms that support several methods nginx will normally
select the most efficient method automatically.
However, if needed, a connection processing method can be selected
explicitly with the
<link doc="ngx_core_module.xml" id="use"/> directive.
</para>

<para>
The following connection processing methods are supported:
<list type="bullet">

<listitem id="select">
<para>
<literal>select</literal>&mdash;standard method.
The supporting module is built automatically on platforms that lack
more efficient methods.
The <literal>--with-select_module</literal> and
<literal>--without-select_module</literal> configuration parameters
can be used to forcibly enable or disable the build of this module.
</para>
</listitem>

<listitem id="poll">
<para>
<literal>poll</literal>&mdash;standard method.
The supporting module is built automatically on platforms that lack
more efficient methods.
The <literal>--with-poll_module</literal> and
<literal>--without-poll_module</literal> configuration parameters
can be used to forcibly enable or disable the build of this module.
</para>
</listitem>

<listitem id="kqueue">
<para>
<literal>kqueue</literal>&mdash;efficient method used on
FreeBSD 4.1+, OpenBSD 2.9+, NetBSD 2.0, and macOS.
</para>
</listitem>

<listitem id="epoll">
<para>
<literal>epoll</literal>&mdash;efficient method used on
Linux 2.6+.
<note>
The <literal>EPOLLRDHUP</literal> (Linux 2.6.17, glibc 2.8)
and <literal>EPOLLEXCLUSIVE</literal> (Linux 4.5, glibc 2.24)
flags are supported since 1.11.3.
</note>
<note>
Some older distributions like SuSE 8.2 provide patches
that add epoll support to 2.4 kernels.
</note>
</para>
</listitem>

<listitem id="devpoll">
<para>
<literal>/dev/poll</literal>&mdash;efficient method used on
Solaris 7 11/99+, HP/UX 11.22+ (eventport), IRIX 6.5.15+,
and Tru64 UNIX 5.1A+.
</para>
</listitem>

<listitem id="eventport">
<para>
<literal>eventport</literal>&mdash;event ports, method
used on Solaris 10+ (due to known issues,
it is recommended using the <literal>/dev/poll</literal> method instead).
</para>
</listitem>

</list>
</para>

</section>

</article>