man: document systemd-oomd and related items

1 files changed, 88 insertions, 0 deletions

diff --git a/man/oomd.conf.xml b/man/oomd.conf.xml
new file mode 100644
index 0000000000..e6be947c5b
--- /dev/null
+++ b/man/oomd.conf.xml
@@ -0,0 +1,88 @@
+<?xml version='1.0'?> <!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
+
+<refentry id="oomd.conf" conditional='ENABLE_OOMD'
+    xmlns:xi="http://www.w3.org/2001/XInclude">
+  <refentryinfo>
+    <title>oomd.conf</title>
+    <productname>systemd</productname>
+  </refentryinfo>
+
+  <refmeta>
+    <refentrytitle>oomd.conf</refentrytitle>
+    <manvolnum>5</manvolnum>
+  </refmeta>
+
+  <refnamediv>
+    <refname>oomd.conf</refname>
+    <refname>oomd.conf.d</refname>
+    <refpurpose>Global <command>systemd-oomd</command> configuration files</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <para><filename>/etc/systemd/oomd.conf</filename></para>
+    <para><filename>/etc/systemd/oomd.conf.d/*.conf</filename></para>
+    <para><filename>/usr/lib/systemd/oomd.conf.d/*.conf</filename></para>
+  </refsynopsisdiv>
+
+  <refsect1>
+    <title>Description</title>
+
+    <para>These files configure the various parameters of the
+    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> userspace
+    out-of-memory (OOM) killer,
+    <citerefentry><refentrytitle>systemd-oomd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
+    See <citerefentry><refentrytitle>systemd.syntax</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+    for a general description of the syntax.</para>
+
+  </refsect1>
+
+  <xi:include href="standard-conf.xml" xpointer="main-conf" />
+
+  <refsect1>
+    <title>[OOM] Section Options</title>
+
+    <para>The following options are available in the [OOM] section:</para>
+
+    <variablelist class='config-directives'>
+      <varlistentry>
+        <term><varname>SwapUsedLimitPercent=</varname></term>
+
+        <listitem><para>Sets the limit for swap usage on the system before <command>systemd-oomd</command> will
+        take action. If the percentage of swap used on the system is more than what is defined here,
+        <command>systemd-oomd</command> will act on eligible descendant cgroups, starting from the ones with the
+        highest swap usage to the lowest swap usage. Which cgroups are monitored and what
+        action gets taken depends on what the unit has configured for <varname>ManagedOOMSwap=</varname>.
+        Takes a percentage value between 0% and 100%, inclusive. Defaults to 90%.</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultMemoryPressureLimitPercent=</varname></term>
+
+        <listitem><para>Sets the limit for memory pressure on the unit's cgroup before <command>systemd-oomd</command>
+        will take action. A unit can override this value with <varname>ManagedOOMMemoryPressureLimitPercent=</varname>.
+        The memory pressure for this property represents the fraction of time in a 10 second window in which all tasks
+        in the cgroup were delayed. For each monitored cgroup, if the memory pressure on that cgroup exceeds the
+        limit set for more than 30 seconds, <command>systemd-oomd</command> will act on eligible descendant cgroups,
+        starting from the ones with the most reclaim activity to the least reclaim activity. Which cgroups are
+        monitored and what action gets taken depends on what the unit has configured for
+        <varname>ManagedOOMMemoryPressure=</varname>. Takes a percentage value between 0% and 100%, inclusive.
+        Defaults to 60%.</para></listitem>
+      </varlistentry>
+
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+      <title>See Also</title>
+      <para>
+        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-oomd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>oomctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+      </para>
+  </refsect1>
+
+</refentry>