From zram documentation: The zram module creates RAM based block devices named /dev/zram<id> (<id> = 0, 1, ...). Pages written to these disks are compressed and stored in memory itself. These disks allow very fast I/O and compression provides good amounts of memory savings. Some of the usecases include /tmp storage, use as swap disks, various caches under /var and maybe many more :)
Example of compressed swap in memory
Write this commands in
/etc/rc.local to create a 2G compressed swap partition in memory.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
# Load the module and create one zram device, /dev/zram0 modprobe zram num_devices=1 # Maximum of compressed streams (keep same as CPUs) echo 4 > /sys/devices/virtual/block/zram0/max_comp_streams # Size of zram0 device in k/m/g echo 2g > /sys/devices/virtual/block/zram0/disksize # Comression compression algorithm to use echo lzo > /sys/devices/virtual/block/zram0/comp_algorithm # Create the swap file system mkswap /dev/zram0 # Enable the swap partition with high priority swapon /dev/zram0 -p 10