1zram: Compressed RAM based block devices
2----------------------------------------
3* Introduction
4
5The zram module creates RAM based block devices named /dev/zram<id>
6(<id> = 0, 1, ...). Pages written to these disks are compressed and stored
7in memory itself. These disks allow very fast I/O and compression provides
8good amounts of memory savings. Some of the usecases include /tmp storage,
9use as swap disks, various caches under /var and maybe many more :)
10
11Statistics for individual zram devices are exported through sysfs nodes at
12/sys/block/zram<id>/
13
14Kconfig required:
15CONFIG_ZRAM=y
16CONFIG_CRYPTO_LZ4=y
17CONFIG_ZPOOL=y
18CONFIG_ZSMALLOC=y
19
20ZRAM Testcases
21--------------
22zram_lib.sh: create library with initialization/cleanup functions
23zram.sh: For sanity check of CONFIG_ZRAM and to run zram01 and zram02
24
25Two functional tests: zram01 and zram02:
26zram01.sh: creates general purpose ram disks with ext4 filesystems
27zram02.sh: creates block device for swap
28
29Commands required for testing:
30 - bc
31 - dd
32 - free
33 - awk
34 - mkswap
35 - swapon
36 - swapoff
37 - mkfs/ mkfs.ext4
38
39For more information please refer:
40kernel-source-tree/Documentation/blockdev/zram.txt
41