настраивать и управлять устройствами Zram (set up and control zram devices)
Имя (Name)
zramctl - set up and control zram devices
Синопсис (Synopsis)
Get info:
zramctl
[options]
Reset zram:
zramctl -r
zramdev...
Print name of first unused zram device:
zramctl -f
Set up a zram device:
zramctl
[-f
| zramdev] [-s
size] [-t
number] [-a
algorithm]
Описание (Description)
zramctl
is used to quickly set up zram device parameters, to
reset zram devices, and to query the status of used zram devices.
If no option is given, all non-zero size zram devices are shown.
Note that zramdev node specified on command line has to already
exist. The command zramctl
creates a new /dev/zram<N> nodes only
when --find
option specified. It's possible (and common) that
after system boot /dev/zram<N> nodes are not created yet.
Параметры (Options)
-a
, --algorithm lzo
|lz4
|lz4hc
|deflate
|842
|zstd
Set the compression algorithm to be used for compressing data
in the zram device.
-f
, --find
Find the first unused zram device. If a --size
argument is
present, then initialize the device.
-n
, --noheadings
Do not print a header line in status output.
-o
, --output
list
Define the status output columns to be used. If no output
arrangement is specified, then a default set is used. Use
--help
to get a list of all supported columns.
--output-all
Output all available columns.
--raw
Use the raw format for status output.
-r
, --reset
Reset the options of the specified zram device(s). Zram
device settings can be changed only after a reset.
-s
, --size
size
Create a zram device of the specified size. Zram devices are
aligned to memory pages; when the requested size is not a
multiple of the page size, it will be rounded up to the next
multiple. When not otherwise specified, the unit of the size
parameter is bytes.
The size argument may be followed by the multiplicative
suffixes KiB (=1024), MiB (=1024*1024), and so on for GiB,
TiB, PiB, EiB, ZiB and YiB (the "iB" is optional, e.g., "K"
has the same meaning as "KiB") or the suffixes KB (=1000), MB
(=1000*1000), and so on for GB, TB, PB, EB, ZB and YB.
-t
, --streams
number
Set the maximum number of compression streams that can be
used for the device. The default is use all CPUs and one
stream for kernels older than 4.6.
-V
, --version
Display version information and exit.
-h
, --help
Display help text and exit.
Статус выхода (Exit)
zramctl
returns 0 on success, nonzero on failure.
Файлы (Files)
/dev/zram[0..N]
zram block devices
Примеры (Examples)
The following commands set up a zram device with a size of one
gigabyte and use it as swap device.
# zramctl --find --size 1024M
/dev/zram0
# mkswap /dev/zram0
# swapon /dev/zram0
...
# swapoff /dev/zram0
# zramctl --reset /dev/zram0