unitfile_rlimit — Resource control unit settings
name.slice ,
name.scope ,
name.service ,
name.socket ,
name.mount ,
name.swap
Unit configuration files for services, slices, scopes, sockets, mount points, and swap devices share a subset of configuration options for resource control of spawned processes. Internally, this relies on the the Control Groups kernel concept for organizing processes in a hierarchial tree of named groups for the purpose of resource management.
This man page lists the configuration options shared by those six unit types. See unitfile(5) for the common options of all unit configuration files, and unitfile_slice(5) , unitfile_scope(5) , unitfile_service(5) , unitfile_socket(5) , unitfile_mount(5) , and unitfile_swap(5) for more information on the specific unit configuration files. The resource control configuration options are configured in the [Slice], [Scope], [Service], [Socket], [Mount], or [Swap] sections, depending on the unit type.
See the New Control Group Interfaces for an introduction how to make use of resource control APIs from programs.
Units of the types listed above can have settings for resource control configuration:
CPUAccounting=
Turn on CPU usage accounting for this unit. Takes a boolean argument. Note that turning on CPU accounting for one unit might also implicitly turn it on for all units contained in the same slice and for all its parent slices and the units contained therein.
CPUShares= weight
Assign the specified overall CPU time share weight to the
processes executed. Takes an integer value. This controls the
cpu.shares control group attribute, which
defaults to 1024. For details about this control group attribute,
see sched-design-CFS.txt
.
Implies CPUAccounting=true .
MemoryAccounting=
Turn on process and kernel memory accounting for this unit. Takes a boolean argument. Note that turning on memory accounting for one unit might also implicitly turn it on for all units contained in the same slice and for all its parent slices and the units contained therein.
MemoryLimit= bytes
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. This controls the
memory.limit_in_bytes control group attribute.
For details about this control group attribute, see memory.txt
.
Implies MemoryAccounting=true .
BlockIOAccounting=
Turn on Block IO accounting for this unit. Takes a boolean argument. Note that turning on block IO accounting for one unit might also implicitly turn it on for all units contained in the same slice and all for its parent slices and the units contained therein.
BlockIOWeight= weight
Set the default overall block IO weight for the executed
processes. Takes a single weight value (between 10 and 1000) to set
the default block IO weight. This controls the
blkio.weight control group attribute, which
defaults to 1000. For details about this control group attribute,
see blkio-controller.txt
.
Implies BlockIOAccounting=true .
BlockIODeviceWeight= device
weight
Set the per-device overall block IO weight for the executed
processes. Takes a space-separated pair of a file path and a weight
value to specify the device specific weight value, between 10 and
1000. (Example: "/dev/sda 500"). The file path may be specified as
path to a block device node or as any other file in which case the
backing block device of the file system of the file is determined.
This controls the blkio.weight_device control
group attribute, which defaults to 1000. Use this option multiple
times to set weights for multiple devices. For details about this
control group attribute, see blkio-controller.txt
.
Implies BlockIOAccounting=true .
BlockIOReadBandwidth= device
bytes
,
BlockIOWriteBandwidth= device
bytes
Set the per-device overall block IO bandwidth limit for the
executed processes. Takes a space-separated pair of a file path and
a bandwidth value (in bytes per second) to specify the device
specific bandwidth. The file path may be a path to a block device
node, or as any other file in which case the backing block device of
the file system of the file is used. If the bandwidth is suffixed
with K, M, G, or T, the specified bandwidth is parsed as Kilobytes,
Megabytes, Gigabytes, or Terabytes, respectively (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls
the blkio.read_bps_device and
blkio.write_bps_device control group attributes.
Use this option multiple times to set bandwidth limits for multiple
devices. For details about these control group attributes, see
blkio-controller.txt
.
Implies BlockIOAccounting=true .
DeviceAllow=
Control access to specific device nodes by the executed
processes. Takes two space-separated strings: a device node path
(such as /dev/null ) followed by a combination
of r , w ,
m to control r eading,
w riting, or creation of the specific device
node by the unit ( m knod), respectively. This
controls the devices.allow and
devices.deny control group attributes. For
details about these control group attributes, see devices.txt
.
DevicePolicy=auto|closed|strict
Control the policy for allowing device access:
strict
means to only allow types of access that are explicitly specified.
closed
in addition, allows access to standard pseudo devices
including /dev/null ,
/dev/zero ,
/dev/full ,
/dev/random , and
/dev/urandom .
auto
in addition, allows access to all devices if no explicit
DeviceAllow= is present. This is the
default.
Slice=
The name of the slice unit to place the unit in. Defaults to
system.slice for all non-instantiated units of
all unit types (except for slice units themselves see below).
Instance units are by default placed in a subslice of
system.slice that is named after the template
name.
This option may be used to arrange systemd units in a hierarchy of slices each of which might have resource settings applied.
For units of type slice, the only accepted value for this setting is the parent slice. Since the name of a slice unit implies the parent slice, it is hence redundant to ever set this parameter directly for slice units.
systemd(1) , unitfile(5) , unitfile_service(5) , unitfile_slice(5) , unitfile_scope(5) , unitfile_socket(5) , unitfile_mount(5) , unitfile_swap(5) , systemd.directives(7) , systemd.special(7) , The documentation for control groups and specific controllers in the Linux kernel: cgroups.txt , cpuacct.txt , memory.txt , blkio-controller.txt .