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| <!-- SPDX-License-Identifier: LGPL-2.1-or-later --> |
| |
| <refentry id="systemd-system.conf" |
| xmlns:xi="http://www.w3.org/2001/XInclude"> |
| <refentryinfo> |
| <title>systemd-system.conf</title> |
| <productname>systemd</productname> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>systemd-system.conf</refentrytitle> |
| <manvolnum>5</manvolnum> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>systemd-system.conf</refname> |
| <refname>system.conf.d</refname> |
| <refname>systemd-user.conf</refname> |
| <refname>user.conf.d</refname> |
| <refpurpose>System and session service manager configuration files</refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv> |
| <para><filename>/etc/systemd/system.conf</filename>, |
| <filename>/etc/systemd/system.conf.d/*.conf</filename>, |
| <filename>/run/systemd/system.conf.d/*.conf</filename>, |
| <filename>/usr/lib/systemd/system.conf.d/*.conf</filename></para> |
| |
| <para><filename>~/.config/systemd/user.conf</filename>, |
| <filename>/etc/systemd/user.conf</filename>, |
| <filename>/etc/systemd/user.conf.d/*.conf</filename>, |
| <filename>/run/systemd/user.conf.d/*.conf</filename>, |
| <filename>/usr/lib/systemd/user.conf.d/*.conf</filename></para> |
| </refsynopsisdiv> |
| |
| <refsect1> |
| <title>Description</title> |
| |
| <para>When run as a system instance, <command>systemd</command> interprets the configuration file |
| <filename>system.conf</filename> and the files in <filename>system.conf.d</filename> directories; when |
| run as a user instance, it interprets the configuration file <filename>user.conf</filename> (either in |
| the home directory of the user, or if not found, under <filename>/etc/systemd/</filename>) and the files |
| in <filename>user.conf.d</filename> directories. These configuration files contain a few settings |
| controlling basic manager operations.</para> |
| |
| <para>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>Options</title> |
| |
| <para>All options are configured in the |
| [Manager] section:</para> |
| |
| <variablelist class='config-directives'> |
| |
| <varlistentry> |
| <term><varname>LogColor=</varname></term> |
| <term><varname>LogLevel=</varname></term> |
| <term><varname>LogLocation=</varname></term> |
| <term><varname>LogTarget=</varname></term> |
| <term><varname>LogTime=</varname></term> |
| <term><varname>DumpCore=yes</varname></term> |
| <term><varname>CrashChangeVT=no</varname></term> |
| <term><varname>CrashShell=no</varname></term> |
| <term><varname>CrashReboot=no</varname></term> |
| <term><varname>ShowStatus=yes</varname></term> |
| <term><varname>DefaultStandardOutput=journal</varname></term> |
| <term><varname>DefaultStandardError=inherit</varname></term> |
| |
| <listitem><para>Configures various parameters of basic manager operation. These options may be overridden by |
| the respective process and kernel command line arguments. See |
| <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> for |
| details.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CtrlAltDelBurstAction=</varname></term> |
| |
| <listitem><para>Defines what action will be performed |
| if user presses Ctrl-Alt-Delete more than 7 times in 2s. |
| Can be set to <literal>reboot-force</literal>, <literal>poweroff-force</literal>, |
| <literal>reboot-immediate</literal>, <literal>poweroff-immediate</literal> |
| or disabled with <literal>none</literal>. Defaults to |
| <literal>reboot-force</literal>. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CPUAffinity=</varname></term> |
| |
| <listitem><para>Configures the CPU affinity for the service manager as well as the default CPU |
| affinity for all forked off processes. Takes a list of CPU indices or ranges separated by either |
| whitespace or commas. CPU ranges are specified by the lower and upper CPU indices separated by a |
| dash. This option may be specified more than once, in which case the specified CPU affinity masks are |
| merged. If the empty string is assigned, the mask is reset, all assignments prior to this will have |
| no effect. Individual services may override the CPU affinity for their processes with the |
| <varname>CPUAffinity=</varname> setting in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NUMAPolicy=</varname></term> |
| |
| <listitem><para>Configures the NUMA memory policy for the service manager and the default NUMA memory policy |
| for all forked off processes. Individual services may override the default policy with the |
| <varname>NUMAPolicy=</varname> setting in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NUMAMask=</varname></term> |
| |
| <listitem><para>Configures the NUMA node mask that will be associated with the selected NUMA policy. Note that |
| <option>default</option> and <option>local</option> NUMA policies don't require explicit NUMA node mask and |
| value of the option can be empty. Similarly to <varname>NUMAPolicy=</varname>, value can be overridden |
| by individual services in unit files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>RuntimeWatchdogSec=</varname></term> |
| <term><varname>RebootWatchdogSec=</varname></term> |
| <term><varname>KExecWatchdogSec=</varname></term> |
| |
| <listitem><para>Configure the hardware watchdog at runtime and at reboot. Takes a timeout value in |
| seconds (or in other time units if suffixed with <literal>ms</literal>, <literal>min</literal>, |
| <literal>h</literal>, <literal>d</literal>, <literal>w</literal>), or the special strings |
| <literal>off</literal> or <literal>default</literal>. If set to <literal>off</literal> |
| (alternatively: <literal>0</literal>) the watchdog logic is disabled: no watchdog device is opened, |
| configured, or pinged. If set to the special string <literal>default</literal> the watchdog is opened |
| and pinged in regular intervals, but the timeout is not changed from the default. If set to any other |
| time value the watchdog timeout is configured to the specified value (or a value close to it, |
| depending on hardware capabilities).</para> |
| |
| <para>If <varname>RuntimeWatchdogSec=</varname> is set to a non-zero value, the watchdog hardware |
| (<filename>/dev/watchdog0</filename> or the path specified with <varname>WatchdogDevice=</varname> or |
| the kernel option <varname>systemd.watchdog-device=</varname>) will be programmed to automatically |
| reboot the system if it is not contacted within the specified timeout interval. The system manager |
| will ensure to contact it at least once in half the specified timeout interval. This feature requires |
| a hardware watchdog device to be present, as it is commonly the case in embedded and server |
| systems. Not all hardware watchdogs allow configuration of all possible reboot timeout values, in |
| which case the closest available timeout is picked.</para> |
| |
| <para><varname>RebootWatchdogSec=</varname> may be used to configure the hardware watchdog when the |
| system is asked to reboot. It works as a safety net to ensure that the reboot takes place even if a |
| clean reboot attempt times out. Note that the <varname>RebootWatchdogSec=</varname> timeout applies |
| only to the second phase of the reboot, i.e. after all regular services are already terminated, and |
| after the system and service manager process (PID 1) got replaced by the |
| <filename>systemd-shutdown</filename> binary, see system |
| <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> for |
| details. During the first phase of the shutdown operation the system and service manager remains |
| running and hence <varname>RuntimeWatchdogSec=</varname> is still honoured. In order to define a |
| timeout on this first phase of system shutdown, configure <varname>JobTimeoutSec=</varname> and |
| <varname>JobTimeoutAction=</varname> in the [Unit] section of the |
| <filename>shutdown.target</filename> unit. By default <varname>RuntimeWatchdogSec=</varname> defaults |
| to 0 (off), and <varname>RebootWatchdogSec=</varname> to 10min.</para> |
| |
| <para><varname>KExecWatchdogSec=</varname> may be used to additionally enable the watchdog when kexec |
| is being executed rather than when rebooting. Note that if the kernel does not reset the watchdog on |
| kexec (depending on the specific hardware and/or driver), in this case the watchdog might not get |
| disabled after kexec succeeds and thus the system might get rebooted, unless |
| <varname>RuntimeWatchdogSec=</varname> is also enabled at the same time. For this reason it is |
| recommended to enable <varname>KExecWatchdogSec=</varname> only if |
| <varname>RuntimeWatchdogSec=</varname> is also enabled.</para> |
| |
| <para>These settings have no effect if a hardware watchdog is not available.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>RuntimeWatchdogPreSec=</varname></term> |
| |
| <listitem><para>Configure the hardware watchdog device pre-timeout value. |
| Takes a timeout value in seconds (or in other time units similar to |
| <varname>RuntimeWatchdogSec=</varname>). A watchdog pre-timeout is a |
| notification generated by the watchdog before the watchdog reset might |
| occur in the event the watchdog has not been serviced. This notification |
| is handled by the kernel and can be configured to take an action (i.e. |
| generate a kernel panic) using <varname>RuntimeWatchdogPreGovernor=</varname>. |
| Not all watchdog hardware or drivers support generating a pre-timeout and |
| depending on the state of the system, the kernel may be unable to take the |
| configured action before the watchdog reboot. The watchdog will be configured |
| to generate the pre-timeout event at the amount of time specified by |
| <varname>RuntimeWatchdogPreSec=</varname> before the runtime watchdog timeout |
| (set by <varname>RuntimeWatchdogSec=</varname>). For example, if the we have |
| <varname>RuntimeWatchdogSec=30</varname> and |
| <varname>RuntimeWatchdogPreSec=10</varname>, then the pre-timeout event |
| will occur if the watchdog has not pinged for 20s (10s before the |
| watchdog would fire). By default, <varname>RuntimeWatchdogPreSec=</varname> |
| defaults to 0 (off). The value set for <varname>RuntimeWatchdogPreSec=</varname> |
| must be smaller than the timeout value for <varname>RuntimeWatchdogSec=</varname>. |
| This setting has no effect if a hardware watchdog is not available or the |
| hardware watchdog does not support a pre-timeout and will be ignored by the |
| kernel if the setting is greater than the actual watchdog timeout.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>RuntimeWatchdogPreGovernor=</varname></term> |
| |
| <listitem><para>Configure the action taken by the hardware watchdog device |
| when the pre-timeout expires. The default action for the pre-timeout event |
| depends on the kernel configuration, but it is usually to log a kernel |
| message. For a list of valid actions available for a given watchdog device, |
| check the content of the |
| <filename>/sys/class/watchdog/watchdog<replaceable>X</replaceable>/pretimeout_available_governors</filename> |
| file. Typically, available governor types are <varname>noop</varname> and <varname>panic</varname>. |
| Availability, names and functionality might vary depending on the specific device driver |
| in use. If the <filename>pretimeout_available_governors</filename> sysfs file is empty, |
| the governor might be built as a kernel module and might need to be manually loaded |
| (e.g. <varname>pretimeout_noop.ko</varname>), or the watchdog device might not support |
| pre-timeouts.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>WatchdogDevice=</varname></term> |
| |
| <listitem><para>Configure the hardware watchdog device that the |
| runtime and shutdown watchdog timers will open and use. Defaults |
| to <filename>/dev/watchdog0</filename>. This setting has no |
| effect if a hardware watchdog is not available.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>CapabilityBoundingSet=</varname></term> |
| |
| <listitem><para>Controls which capabilities to include in the |
| capability bounding set for PID 1 and its children. See |
| <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| for details. Takes a whitespace-separated list of capability |
| names as read by |
| <citerefentry project='mankier'><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>. |
| Capabilities listed will be included in the bounding set, all |
| others are removed. If the list of capabilities is prefixed |
| with ~, all but the listed capabilities will be included, the |
| effect of the assignment inverted. Note that this option also |
| affects the respective capabilities in the effective, |
| permitted and inheritable capability sets. The capability |
| bounding set may also be individually configured for units |
| using the <varname>CapabilityBoundingSet=</varname> directive |
| for units, but note that capabilities dropped for PID 1 cannot |
| be regained in individual units, they are lost for |
| good.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>NoNewPrivileges=</varname></term> |
| |
| <listitem><para>Takes a boolean argument. If true, ensures that PID 1 |
| and all its children can never gain new privileges through |
| <citerefentry project='man-pages'><refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum></citerefentry> |
| (e.g. via setuid or setgid bits, or filesystem capabilities). |
| Defaults to false. General purpose distributions commonly rely |
| on executables with setuid or setgid bits and will thus not |
| function properly with this option enabled. Individual units |
| cannot disable this option. |
| Also see <ulink url="https://docs.kernel.org/userspace-api/no_new_privs.html">No New Privileges Flag</ulink>. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>SystemCallArchitectures=</varname></term> |
| |
| <listitem><para>Takes a space-separated list of architecture |
| identifiers. Selects from which architectures system calls may |
| be invoked on this system. This may be used as an effective |
| way to disable invocation of non-native binaries system-wide, |
| for example to prohibit execution of 32-bit x86 binaries on |
| 64-bit x86-64 systems. This option operates system-wide, and |
| acts similar to the |
| <varname>SystemCallArchitectures=</varname> setting of unit |
| files, see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. This setting defaults to the empty list, in which |
| case no filtering of system calls based on architecture is |
| applied. Known architecture identifiers are |
| <literal>x86</literal>, <literal>x86-64</literal>, |
| <literal>x32</literal>, <literal>arm</literal> and the special |
| identifier <literal>native</literal>. The latter implicitly |
| maps to the native architecture of the system (or more |
| specifically, the architecture the system manager was compiled |
| for). Set this setting to <literal>native</literal> to |
| prohibit execution of any non-native binaries. When a binary |
| executes a system call of an architecture that is not listed |
| in this setting, it will be immediately terminated with the |
| SIGSYS signal.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>TimerSlackNSec=</varname></term> |
| |
| <listitem><para>Sets the timer slack in nanoseconds for PID 1, |
| which is inherited by all executed processes, unless |
| overridden individually, for example with the |
| <varname>TimerSlackNSec=</varname> setting in service units |
| (for details see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>). |
| The timer slack controls the accuracy of wake-ups triggered by |
| system timers. See |
| <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry> |
| for more information. Note that in contrast to most other time |
| span definitions this parameter takes an integer value in |
| nano-seconds if no unit is specified. The usual time units are |
| understood too.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>StatusUnitFormat=</varname></term> |
| |
| <listitem><para>Takes <option>name</option>, <option>description</option> or |
| <option>combined</option> as the value. If <option>name</option>, the system manager will use unit |
| names in status messages (e.g. <literal>systemd-journald.service</literal>), instead of the longer |
| and more informative descriptions set with <varname>Description=</varname> (e.g. <literal>Journal |
| Logging Service</literal>). If <option>combined</option>, the system manager will use both unit names |
| and descriptions in status messages (e.g. <literal>systemd-journald.service - Journal Logging |
| Service</literal>).</para> |
| |
| <para>See |
| <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for |
| details about unit names and <varname>Description=</varname>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTimerAccuracySec=</varname></term> |
| |
| <listitem><para>Sets the default accuracy of timer units. This |
| controls the global default for the |
| <varname>AccuracySec=</varname> setting of timer units, see |
| <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. <varname>AccuracySec=</varname> set in individual |
| units override the global default for the specific unit. |
| Defaults to 1min. Note that the accuracy of timer units is |
| also affected by the configured timer slack for PID 1, see |
| <varname>TimerSlackNSec=</varname> above.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTimeoutStartSec=</varname></term> |
| <term><varname>DefaultTimeoutStopSec=</varname></term> |
| <term><varname>DefaultTimeoutAbortSec=</varname></term> |
| <term><varname>DefaultRestartSec=</varname></term> |
| |
| <listitem><para>Configures the default timeouts for starting, stopping and aborting of units, as well |
| as the default time to sleep between automatic restarts of units, as configured per-unit in |
| <varname>TimeoutStartSec=</varname>, <varname>TimeoutStopSec=</varname>, |
| <varname>TimeoutAbortSec=</varname> and <varname>RestartSec=</varname> (for services, see |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-unit settings). For non-service units, |
| <varname>DefaultTimeoutStartSec=</varname> sets the default <varname>TimeoutSec=</varname> value. |
| </para> |
| |
| <para><varname>DefaultTimeoutStartSec=</varname> and <varname>DefaultTimeoutStopSec=</varname> |
| default to &DEFAULT_TIMEOUT; in the system manager and &DEFAULT_USER_TIMEOUT; in the user manager. |
| <varname>DefaultTimeoutAbortSec=</varname> is not set by default so that all units fall back to |
| <varname>TimeoutStopSec=</varname>. <varname>DefaultRestartSec=</varname> defaults to 100 ms. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultDeviceTimeoutSec=</varname></term> |
| |
| <listitem><para>Configures the default timeout for waiting for devices. It can be changed per |
| device via the <varname>x-systemd.device-timeout=</varname> option in <filename>/etc/fstab</filename> |
| and <filename>/etc/crypttab</filename> (see |
| <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum></citerefentry>). |
| Defaults to &DEFAULT_TIMEOUT; in the system manager and &DEFAULT_USER_TIMEOUT; in the user manager. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultStartLimitIntervalSec=</varname></term> |
| <term><varname>DefaultStartLimitBurst=</varname></term> |
| |
| <listitem><para>Configure the default unit start rate |
| limiting, as configured per-service by |
| <varname>StartLimitIntervalSec=</varname> and |
| <varname>StartLimitBurst=</varname>. See |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-service settings. |
| <varname>DefaultStartLimitIntervalSec=</varname> defaults to |
| 10s. <varname>DefaultStartLimitBurst=</varname> defaults to |
| 5.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultEnvironment=</varname></term> |
| |
| <listitem><para>Configures environment variables passed to all executed processes. Takes a |
| space-separated list of variable assignments. See <citerefentry |
| project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> for |
| details about environment variables.</para> |
| |
| <para>Simple <literal>%</literal>-specifier expansion is supported, see below for a list of supported |
| specifiers.</para> |
| |
| <para>Example: |
| |
| <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting> |
| |
| Sets three variables |
| <literal>VAR1</literal>, |
| <literal>VAR2</literal>, |
| <literal>VAR3</literal>.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>ManagerEnvironment=</varname></term> |
| |
| <listitem><para>Takes the same arguments as <varname>DefaultEnvironment=</varname>, see above. Sets |
| environment variables just for the manager process itself. In contrast to user managers, these variables |
| are not inherited by processes spawned by the system manager, use <varname>DefaultEnvironment=</varname> |
| for that. Note that these variables are merged into the existing environment block. In particular, in |
| case of the system manager, this includes variables set by the kernel based on the kernel command line.</para> |
| |
| <para>Setting environment variables for the manager process may be useful to modify its behaviour. |
| See <ulink url="https://systemd.io/ENVIRONMENT">ENVIRONMENT</ulink> for a descriptions of some |
| variables understood by <command>systemd</command>.</para> |
| |
| <para>Simple <literal>%</literal>-specifier expansion is supported, see below for a list of supported |
| specifiers.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultCPUAccounting=</varname></term> |
| <term><varname>DefaultMemoryAccounting=</varname></term> |
| <term><varname>DefaultTasksAccounting=</varname></term> |
| <term><varname>DefaultIOAccounting=</varname></term> |
| <term><varname>DefaultIPAccounting=</varname></term> |
| |
| <listitem><para>Configure the default resource accounting settings, as configured per-unit by |
| <varname>CPUAccounting=</varname>, <varname>MemoryAccounting=</varname>, |
| <varname>TasksAccounting=</varname>, <varname>IOAccounting=</varname> and |
| <varname>IPAccounting=</varname>. See |
| <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details on the per-unit settings. <varname>DefaultTasksAccounting=</varname> defaults to yes, |
| <varname>DefaultMemoryAccounting=</varname> to &MEMORY_ACCOUNTING_DEFAULT;. |
| <varname>DefaultCPUAccounting=</varname> defaults to yes, but really has no effect if enabling CPU |
| accounting doesn't require the <option>cpu</option> controller to be enabled (Linux 4.15+ using the |
| unified hierarchy for resource control), otherwise it defaults to no. The other three settings |
| default to no.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultTasksMax=</varname></term> |
| |
| <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See |
| <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. This setting applies to all unit types that support resource control settings, with the exception |
| of slice units. Defaults to 15% of the minimum of <varname>kernel.pid_max=</varname>, <varname>kernel.threads-max=</varname> |
| and root cgroup <varname>pids.max</varname>. |
| Kernel has a default value for <varname>kernel.pid_max=</varname> and an algorithm of counting in case of more than 32 cores. |
| For example, with the default <varname>kernel.pid_max=</varname>, <varname>DefaultTasksMax=</varname> defaults to 4915, |
| but might be greater in other systems or smaller in OS containers.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultLimitCPU=</varname></term> |
| <term><varname>DefaultLimitFSIZE=</varname></term> |
| <term><varname>DefaultLimitDATA=</varname></term> |
| <term><varname>DefaultLimitSTACK=</varname></term> |
| <term><varname>DefaultLimitCORE=</varname></term> |
| <term><varname>DefaultLimitRSS=</varname></term> |
| <term><varname>DefaultLimitNOFILE=</varname></term> |
| <term><varname>DefaultLimitAS=</varname></term> |
| <term><varname>DefaultLimitNPROC=</varname></term> |
| <term><varname>DefaultLimitMEMLOCK=</varname></term> |
| <term><varname>DefaultLimitLOCKS=</varname></term> |
| <term><varname>DefaultLimitSIGPENDING=</varname></term> |
| <term><varname>DefaultLimitMSGQUEUE=</varname></term> |
| <term><varname>DefaultLimitNICE=</varname></term> |
| <term><varname>DefaultLimitRTPRIO=</varname></term> |
| <term><varname>DefaultLimitRTTIME=</varname></term> |
| |
| <listitem><para>These settings control various default resource limits for processes executed by |
| units. See |
| <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry> for |
| details. These settings may be overridden in individual units using the corresponding |
| <varname>LimitXXX=</varname> directives and they accept the same parameter syntax, |
| see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. Note that these resource limits are only defaults |
| for units, they are not applied to the service manager process (i.e. PID 1) itself.</para> |
| |
| <para>Most of these settings are unset, which means the resource limits are inherited from the kernel or, if |
| invoked in a container, from the container manager. However, the following have defaults:</para> |
| <itemizedlist> |
| <listitem><para><varname>DefaultLimitNOFILE=</varname> defaults to 1024:&HIGH_RLIMIT_NOFILE;. |
| </para></listitem> |
| |
| <listitem><para><varname>DefaultLimitMEMLOCK=</varname> defaults to 8M.</para></listitem> |
| |
| <listitem><para><varname>DefaultLimitCORE=</varname> does not have a default but it is worth mentioning that |
| <varname>RLIMIT_CORE</varname> is set to <literal>infinity</literal> by PID 1 which is inherited by its |
| children.</para></listitem> |
| </itemizedlist> |
| |
| <para>Note that the service manager internally in PID 1 bumps <varname>RLIMIT_NOFILE</varname> and |
| <varname>RLIMIT_MEMLOCK</varname> to higher values, however the limit is reverted to the mentioned |
| defaults for all child processes forked off.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultOOMPolicy=</varname></term> |
| |
| <listitem><para>Configure the default policy for reacting to processes being killed by the Linux |
| Out-Of-Memory (OOM) killer or <command>systemd-oomd</command>. This may be used to pick a global default for the per-unit |
| <varname>OOMPolicy=</varname> setting. See |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details. Note that this default is not used for services that have <varname>Delegate=</varname> |
| turned on.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultOOMScoreAdjust=</varname></term> |
| |
| <listitem><para>Configures the default OOM score adjustments of processes run by the service |
| manager. This defaults to unset (meaning the forked off processes inherit the service manager's OOM |
| score adjustment value), except if the service manager is run for an unprivileged user, in which case |
| this defaults to the service manager's OOM adjustment value plus 100 (this makes service processes |
| slightly more likely to be killed under memory pressure than the manager itself). This may be used to |
| pick a global default for the per-unit <varname>OOMScoreAdjust=</varname> setting. See |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for |
| details. Note that this setting has no effect on the OOM score adjustment value of the service |
| manager process itself, it retains the original value set during its invocation.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>DefaultSmackProcessLabel=</varname></term> |
| |
| <listitem><para>Takes a <option>SMACK64</option> security label as the argument. The process executed |
| by a unit will be started under this label if <varname>SmackProcessLabel=</varname> is not set in the |
| unit. See <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for the details.</para> |
| |
| <para>If the value is <literal>/</literal>, only labels specified with <varname>SmackProcessLabel=</varname> |
| are assigned and the compile-time default is ignored.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><varname>ReloadLimitIntervalSec=</varname></term> |
| <term><varname>ReloadLimitBurst=</varname></term> |
| |
| <listitem><para>Rate limiting for daemon-reload requests. Default to unset, and any number of daemon-reload |
| operations can be requested at any time. <varname>ReloadLimitIntervalSec=</varname> takes a value in seconds |
| to configure the rate limit window, and <varname>ReloadLimitBurst=</varname> takes a positive integer to |
| configure the maximum allowed number of reloads within the configured time window.</para></listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>Specifiers</title> |
| |
| <para>Specifiers may be used in the <varname>DefaultEnvironment=</varname> and |
| <varname>ManagerEnvironment=</varname> settings. The following expansions are understood:</para> |
| <table class='specifiers'> |
| <title>Specifiers available</title> |
| <tgroup cols='3' align='left' colsep='1' rowsep='1'> |
| <colspec colname="spec" /> |
| <colspec colname="mean" /> |
| <colspec colname="detail" /> |
| <thead> |
| <row> |
| <entry>Specifier</entry> |
| <entry>Meaning</entry> |
| <entry>Details</entry> |
| </row> |
| </thead> |
| <tbody> |
| <xi:include href="standard-specifiers.xml" xpointer="a"/> |
| <xi:include href="standard-specifiers.xml" xpointer="A"/> |
| <xi:include href="standard-specifiers.xml" xpointer="b"/> |
| <xi:include href="standard-specifiers.xml" xpointer="B"/> |
| <xi:include href="standard-specifiers.xml" xpointer="H"/> |
| <xi:include href="standard-specifiers.xml" xpointer="l"/> |
| <xi:include href="standard-specifiers.xml" xpointer="m"/> |
| <xi:include href="standard-specifiers.xml" xpointer="M"/> |
| <xi:include href="standard-specifiers.xml" xpointer="o"/> |
| <xi:include href="standard-specifiers.xml" xpointer="v"/> |
| <xi:include href="standard-specifiers.xml" xpointer="w"/> |
| <xi:include href="standard-specifiers.xml" xpointer="W"/> |
| <xi:include href="standard-specifiers.xml" xpointer="T"/> |
| <xi:include href="standard-specifiers.xml" xpointer="V"/> |
| <xi:include href="standard-specifiers.xml" xpointer="percent"/> |
| </tbody> |
| </tgroup> |
| </table> |
| </refsect1> |
| |
| <refsect1> |
| <title>History</title> |
| |
| <variablelist> |
| <varlistentry> |
| <term>systemd 252</term> |
| <listitem><para>Option <varname>DefaultBlockIOAccounting=</varname> was deprecated. Please switch |
| to the unified cgroup hierarchy.</para></listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>See Also</title> |
| <para> |
| <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
| <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
| </para> |
| </refsect1> |
| |
| </refentry> |
