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  zram: Compressed RAM based block devices
  ----------------------------------------
  * Introduction
  
  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 :)
  
  Statistics for individual zram devices are exported through sysfs nodes at
  /sys/block/zram<id>/
  
  Kconfig required:
  CONFIG_ZRAM=y
  CONFIG_ZRAM_LZ4_COMPRESS=y
  CONFIG_ZPOOL=y
  CONFIG_ZSMALLOC=y
  
  ZRAM Testcases
  --------------
  zram_lib.sh: create library with initialization/cleanup functions
  zram.sh: For sanity check of CONFIG_ZRAM and to run zram01 and zram02
  
  Two functional tests: zram01 and zram02:
  zram01.sh: creates general purpose ram disks with ext4 filesystems
  zram02.sh: creates block device for swap
  
  Commands required for testing:
   - bc
   - dd
   - free
   - awk
   - mkswap
   - swapon
   - swapoff
   - mkfs/ mkfs.ext4
  
  For more information please refer:
  kernel-source-tree/Documentation/blockdev/zram.txt