zramctl

Check if zram is enabled

$ lsmod | grep -i zram

$ sudo modprobe zram

$ sudo modprobe zram num_devices=2

$ sudo zramctl -f -s 2GB -a lz4

$ sudo zramctl

zramctl [options] [zram-device]

zramctl sets up and controls zram devices, which are compressed RAM-based block devices. Zram is useful for creating compressed swap space or temporary filesystems, improving memory efficiency.
After creating a zram device with zramctl, use mkswap and swapon to use it as swap, or mkfs to create a filesystem.

-f, --find

Find and initialize the next free zram device

Set the size of the zram device

Set compression algorithm (lz4, lzo, zstd, etc.)

Set number of compression streams

Reset the device

Define output columns

Raw output format

Requires the zram kernel module. Compression algorithms vary by kernel version. Zram swap can improve performance on memory-constrained systems but uses CPU for compression. Part of the util-linux package.

mkswap(8), swapon(8), free(1)