NAME

       oomd.conf, oomd.conf.d - Global systemd-oomd configuration files

SYNOPSIS

       /etc/systemd/oomd.conf

       /etc/systemd/oomd.conf.d/*.conf

       /usr/lib/systemd/oomd.conf.d/*.conf

DESCRIPTION

       These files configure the various parameters of the systemd(1) userspace out-of-memory (OOM) killer,
       systemd-oomd.service(8). See systemd.syntax(7) for a general description of the syntax.

CONFIGURATION DIRECTORIES AND PRECEDENCE

       The default configuration is set during compilation, so configuration is only needed when it is necessary
       to deviate from those defaults. The main configuration file is either in /usr/lib/systemd/ or
       /etc/systemd/ and contains commented out entries showing the defaults as a guide to the administrator.
       Local overrides can be created by creating drop-ins, as described below. The main configuration file can
       also be edited for this purpose (or a copy in /etc/ if it's shipped in /usr/) however using drop-ins for
       local configuration is recommended over modifications to the main configuration file.

       In addition to the "main" configuration file, drop-in configuration snippets are read from
       /usr/lib/systemd/*.conf.d/, /usr/local/lib/systemd/*.conf.d/, and /etc/systemd/*.conf.d/. Those drop-ins
       have higher precedence and override the main configuration file. Files in the *.conf.d/ configuration
       subdirectories are sorted by their filename in lexicographic order, regardless of in which of the
       subdirectories they reside. When multiple files specify the same option, for options which accept just a
       single value, the entry in the file sorted last takes precedence, and for options which accept a list of
       values, entries are collected as they occur in the sorted files.

       When packages need to customize the configuration, they can install drop-ins under /usr/. Files in /etc/
       are reserved for the local administrator, who may use this logic to override the configuration files
       installed by vendor packages. Drop-ins have to be used to override package drop-ins, since the main
       configuration file has lower precedence. It is recommended to prefix all filenames in those
       subdirectories with a two-digit number and a dash, to simplify the ordering of the files. This also
       defined a concept of drop-in priority to allow distributions to ship drop-ins within a specific range
       lower than the range used by users. This should lower the risk of package drop-ins overriding
       accidentally drop-ins defined by users.

       To disable a configuration file supplied by the vendor, the recommended way is to place a symlink to
       /dev/null in the configuration directory in /etc/, with the same filename as the vendor configuration
       file.

[OOM] SECTION OPTIONS

       The following options are available in the [OOM] section:

       SwapUsedLimit=
           Sets the limit for memory and swap usage on the system before systemd-oomd will take action. If the
           fraction of memory used and the fraction of swap used on the system are both more than what is
           defined here, systemd-oomd will act on eligible descendant control groups with swap usage greater
           than 5% of total swap, starting from the ones with the highest swap usage. Which control groups are
           monitored and what action gets taken depends on what the unit has configured for ManagedOOMSwap=.
           Takes a value specified in percent (when suffixed with "%"), permille ("‰") or permyriad ("‱"),
           between 0% and 100%, inclusive. Defaults to 90%.

           Added in version 247.

       DefaultMemoryPressureLimit=
           Sets the limit for memory pressure on the unit's control group before systemd-oomd will take action.
           A unit can override this value with ManagedOOMMemoryPressureLimit=. The memory pressure for this
           property represents the fraction of time in a 10 second window in which all tasks in the control
           group were delayed. For each monitored control group, if the memory pressure on that control group
           exceeds the limit set for longer than the duration set by DefaultMemoryPressureDurationSec=,
           systemd-oomd will act on eligible descendant control groups, starting from the ones with the most
           reclaim activity to the least reclaim activity. Which control groups are monitored and what action
           gets taken depends on what the unit has configured for ManagedOOMMemoryPressure=. Takes a fraction
           specified in the same way as SwapUsedLimit= above. Defaults to 60%.

           Added in version 247.

       DefaultMemoryPressureDurationSec=
           Sets the amount of time a unit's control group needs to have exceeded memory pressure limits before
           systemd-oomd will take action. Memory pressure limits are defined by DefaultMemoryPressureLimit= and
           ManagedOOMMemoryPressureLimit=. Must be set to 0, or at least 1 second. Defaults to 30 seconds when
           unset or 0.

           Added in version 248.

SEE ALSO

       systemd(1), systemd.resource-control(5), systemd-oomd.service(8), oomctl(1)