trusty (5) systemd-system.conf.5.gz

NAME

       systemd-system.conf, systemd-user.conf - System and session service manager configuration file

SYNOPSIS

       /etc/systemd/system.conf

       /etc/systemd/user.conf

DESCRIPTION

       When run as system instance systemd reads the configuration file system.conf, otherwise user.conf. These
       configuration files contain a few settings controlling basic manager operations.

OPTIONS

       All options are configured in the [Manager] section:

       LogLevel=, LogTarget=, LogColor=, LogLocation=, DumpCore=yes, CrashShell=no, ShowStatus=yes, CrashChVT=1,
       DefaultStandardOutput=journal, DefaultStandardError=inherit
           Configures various parameters of basic manager operation. These options may be overridden by the
           respective command line arguments. See systemd(1) for details about these command line arguments.

       CPUAffinity=
           Configures the initial CPU affinity for the init process. Takes a space-separated list of CPU
           indexes.

       DefaultControllers=cpu
           Configures in which control group hierarchies to create per-service cgroups automatically, in
           addition to the name=systemd named hierarchy. Defaults to cpu. Takes a space separated list of
           controller names. Pass the empty string to ensure that systemd does not touch any hierarchies but its
           own.

           Note that the default value of 'cpu' will make realtime scheduling unavailable to system services.
           See My Service Can't Get Realtime![1] for more information.

       JoinControllers=cpu,cpuacct,cpuset net_cls,netprio
           Configures controllers that shall be mounted in a single hierarchy. By default systemd will mount all
           controllers which are enabled in the kernel in individual hierarchies, with the exception of those
           listed in this setting. Takes a space separated list of comma separated controller names, in order to
           allow multiple joined hierarchies. Defaults to 'cpu,cpuacct'. Pass an empty string to ensure that
           systemd mounts all controllers in separate hierarchies.

           Note that this option is only applied once, at very early boot. If you use an initial RAM disk
           (initrd) that uses systemd it might hence be necessary to rebuild the initrd if this option is
           changed, and make sure the new configuration file is included in it. Otherwise the initrd might mount
           the controller hierarchies in a different configuration than intended, and the main system cannot
           remount them anymore.

       RuntimeWatchdogSec=, ShutdownWatchdogSec=
           Configure the hardware watchdog at runtime and at reboot. Takes a timeout value in seconds (or in
           other time units if suffixed with ms, min, h, d, w). If RuntimeWatchdogSec= is set to a non-zero
           value the watchdog hardware (/dev/watchdog) 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 the reboot timeout, in which case the closest available timeout is
           picked.  ShutdownWatchdogSec= 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. By default RuntimeWatchdogSec= defaults to 0 (off), and ShutdownWatchdogSec= to
           10min. These settings have no effect if a hardware watchdog is not available.

       CapabilityBoundingSet=
           Controls which capabilities to include in the capability bounding set for PID 1 and its children. See
           capabilities(7) for details. Takes a whitespace separated list of capability names as read by
           cap_from_name(3). 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 CapabilityBoundingSet= directive for units, but note that
           capabilities dropped for PID 1 cannot be regained in individual units, they are lost for good.

       TimerSlackNSec=
           Sets the timer slack in nanoseconds for PID 1 which is then inherited to all executed processes,
           unless overridden individually, for example with the TimerSlackNSec= setting in service units (for
           details see systemd.exec(5)). The timer slack controls the accuracy of wake-ups triggered by timers.
           See prctl(2) 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.

       DefaultLimitCPU=, DefaultLimitFSIZE=, DefaultLimitDATA=, DefaultLimitSTACK=, DefaultLimitCORE=,
       DefaultLimitRSS=, DefaultLimitNOFILE=, DefaultLimitAS=, DefaultLimitNPROC=, DefaultLimitMEMLOCK=,
       DefaultLimitLOCKS=, DefaultLimitSIGPENDING=, DefaultLimitMSGQUEUE=, DefaultLimitNICE=,
       DefaultLimitRTPRIO=, DefaultLimitRTTIME=
           These settings control various default resource limits for units. See setrlimit(2) for details. Use
           the string infinity to configure no limit on a specific resource. These settings may be overridden in
           individual units using the corresponding LimitXXX= directives. Note that these resource limits are
           only defaults for units, they are not applied to PID 1 itself.

SEE ALSO

       systemd(1), systemd.directives(7)

NOTES

        1. My Service Can't Get Realtime!
           http://www.freedesktop.org/wiki/Software/systemd/MyServiceCantGetRealtime