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Diffstat (limited to 'man/systemd.resource-control.xml')
| -rw-r--r-- | man/systemd.resource-control.xml | 75 |
1 files changed, 40 insertions, 35 deletions
diff --git a/man/systemd.resource-control.xml b/man/systemd.resource-control.xml index d4c8fa7091..0e98ca78b8 100644 --- a/man/systemd.resource-control.xml +++ b/man/systemd.resource-control.xml @@ -92,18 +92,17 @@ <refsect1> <title>Automatic Dependencies</title> - <para>Units with the <varname>Slice=</varname> setting set get - automatic <varname>Requires=</varname> and - <varname>After=</varname> dependencies on the specified slice - unit.</para> + <para>Units with the <varname>Slice=</varname> setting set automatically acquire <varname>Requires=</varname> and + <varname>After=</varname> dependencies on the specified slice unit.</para> </refsect1> <refsect1> <title>Unified and Legacy Control Group Hierarchies</title> - <para>Unified control group hierarchy is the new version of kernel control group interface. Depending on the - resource type, there are differences in resource control capabilities. Also, because of interface changes, some - resource types have a separate set of options on the unified hierarchy.</para> + <para>The unified control group hierarchy is the new version of kernel control group interface, see <ulink + url="https://www.kernel.org/doc/Documentation/cgroup-v2.txt">cgroup-v2.txt</ulink>. Depending on the resource type, + there are differences in resource control capabilities. Also, because of interface changes, some resource types + have separate set of options on the unified hierarchy.</para> <para> <variablelist> @@ -117,8 +116,8 @@ <varlistentry> <term><option>Memory</option></term> <listitem> - <para><varname>MemoryMax</varname> replaces <varname>MemoryLimit</varname>. <varname>MemoryLow</varname> - and <varname>MemoryHigh</varname> are effective only on unified hierarchy.</para> + <para><varname>MemoryMax=</varname> replaces <varname>MemoryLimit=</varname>. <varname>MemoryLow=</varname> + and <varname>MemoryHigh=</varname> are effective only on unified hierarchy.</para> </listitem> </varlistentry> </variablelist> @@ -128,6 +127,13 @@ settings of a unit for a given resource type are for the other hierarchy type, the settings are translated and applied. If there are any valid settings for the hierarchy in use, all translations are disabled for the resource type. Mixing the two types of settings on a unit can lead to confusing results.</para> + + <para>Legacy control group hierarchy (see <ulink + url="https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt">cgroups.txt</ulink>), also called cgroup-v1, + doesn't allow safe delegation of controllers to unprivileged processes. If the system uses the legacy control group + hierarchy, resource control is disabled for systemd user instance, see + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>. + </para> </refsect1> <refsect1> @@ -228,9 +234,11 @@ reclaimed as long as memory can be reclaimed from unprotected units.</para> <para>Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is - parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. This controls the - <literal>memory.low</literal> control group attribute. For details about this control group attribute, see - <ulink url="https://www.kernel.org/doc/Documentation/cgroup-v2.txt">cgroup-v2.txt</ulink>.</para> + parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. Alternatively, a + percentage value may be specified, which is taken relative to the installed physical memory on the + system. This controls the <literal>memory.low</literal> control group attribute. For details about this + control group attribute, see <ulink + url="https://www.kernel.org/doc/Documentation/cgroup-v2.txt">cgroup-v2.txt</ulink>.</para> <para>Implies <literal>MemoryAccounting=true</literal>.</para> @@ -247,7 +255,9 @@ aggressively in such cases. This is the main mechanism to control memory usage of a unit.</para> <para>Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is - parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. If assigned the + parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. Alternatively, a + percentage value may be specified, which is taken relative to the installed physical memory on the + system. If assigned the special value <literal>infinity</literal>, no memory limit is applied. This controls the <literal>memory.high</literal> control group attribute. For details about this control group attribute, see <ulink url="https://www.kernel.org/doc/Documentation/cgroup-v2.txt">cgroup-v2.txt</ulink>.</para> @@ -268,8 +278,9 @@ last line of defense.</para> <para>Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is - parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. If assigned the - special value <literal>infinity</literal>, no memory limit is applied. This controls the + parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. Alternatively, a + percentage value may be specified, which is taken relative to the installed physical memory on the system. If + assigned the special value <literal>infinity</literal>, no memory limit is applied. This controls the <literal>memory.max</literal> control group attribute. For details about this control group attribute, see <ulink url="https://www.kernel.org/doc/Documentation/cgroup-v2.txt">cgroup-v2.txt</ulink>.</para> @@ -284,17 +295,14 @@ <term><varname>MemoryLimit=<replaceable>bytes</replaceable></varname></term> <listitem> - <para>Specify the limit on maximum memory usage of the - executed processes. The limit specifies how much process and - kernel memory can be used by tasks in this unit. Takes a - memory size in bytes. If the value is suffixed with K, M, G - or T, the specified memory size is parsed as Kilobytes, - Megabytes, Gigabytes, or Terabytes (with the base 1024), - respectively. If assigned the special value - <literal>infinity</literal>, no memory limit is applied. This - controls the <literal>memory.limit_in_bytes</literal> - control group attribute. For details about this control - group attribute, see <ulink + <para>Specify the limit on maximum memory usage of the executed processes. The limit specifies how much + process and kernel memory can be used by tasks in this unit. Takes a memory size in bytes. If the value is + suffixed with K, M, G or T, the specified memory size is parsed as Kilobytes, Megabytes, Gigabytes, or + Terabytes (with the base 1024), respectively. Alternatively, a percentage value may be specified, which is + taken relative to the installed physical memory on the system. If assigned the special value + <literal>infinity</literal>, no memory limit is applied. This controls the + <literal>memory.limit_in_bytes</literal> control group attribute. For details about this control group + attribute, see <ulink url="https://www.kernel.org/doc/Documentation/cgroup-v1/memory.txt">memory.txt</ulink>.</para> <para>Implies <literal>MemoryAccounting=true</literal>.</para> @@ -327,15 +335,12 @@ <term><varname>TasksMax=<replaceable>N</replaceable></varname></term> <listitem> - <para>Specify the maximum number of tasks that may be - created in the unit. This ensures that the number of tasks - accounted for the unit (see above) stays below a specific - limit. If assigned the special value - <literal>infinity</literal>, no tasks limit is applied. This - controls the <literal>pids.max</literal> control group - attribute. For details about this control group attribute, - see <ulink - url="https://www.kernel.org/doc/Documentation/cgroup-v1/pids.txt">pids.txt</ulink>.</para> + <para>Specify the maximum number of tasks that may be created in the unit. This ensures that the number of + tasks accounted for the unit (see above) stays below a specific limit. This either takes an absolute number + of tasks or a percentage value that is taken relative to the configured maximum number of tasks on the + system. If assigned the special value <literal>infinity</literal>, no tasks limit is applied. This controls + the <literal>pids.max</literal> control group attribute. For details about this control group attribute, see + <ulink url="https://www.kernel.org/doc/Documentation/cgroup-v1/pids.txt">pids.txt</ulink>.</para> <para>Implies <literal>TasksAccounting=true</literal>. The system default for this setting may be controlled with |