zramctl — set up and control zram devices
−f | zramdev ] [
−s size ] [
−t number ] [
−a algorithm ]
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 zram devices are shown.
−a, −−algorithm lzo|lz4
Set the compression algorithm to be used for compressing data in the zram device.
Find the first unused zram device. If a
−−size argument is present,
then initialize the device.
Do not print a header line in status output.
Define the status output columns to be used. If no
output arrangement is specified, then a default set is
−−help to get a list of all
Use the raw format for status output.
Reset the options of the specified zram device(s). Zram device settings can be changed only after a reset.
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
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.
Set the maximum number of compression streams that can be used for the device. The default is one stream.
Display version information and exit.
Display help text and exit.
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