2015-08-18 15:01:59 +08:00
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zram: Compressed RAM based block devices
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* Introduction
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The zram module creates RAM based block devices named /dev/zram<id>
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(<id> = 0, 1, ...). Pages written to these disks are compressed and stored
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in memory itself. These disks allow very fast I/O and compression provides
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good amounts of memory savings. Some of the usecases include /tmp storage,
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use as swap disks, various caches under /var and maybe many more :)
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Statistics for individual zram devices are exported through sysfs nodes at
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/sys/block/zram<id>/
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Kconfig required:
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CONFIG_ZRAM=y
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2016-08-13 04:49:59 +08:00
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CONFIG_CRYPTO_LZ4=y
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2015-08-18 15:01:59 +08:00
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CONFIG_ZPOOL=y
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CONFIG_ZSMALLOC=y
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ZRAM Testcases
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--------------
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zram_lib.sh: create library with initialization/cleanup functions
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zram.sh: For sanity check of CONFIG_ZRAM and to run zram01 and zram02
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Two functional tests: zram01 and zram02:
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zram01.sh: creates general purpose ram disks with ext4 filesystems
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zram02.sh: creates block device for swap
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Commands required for testing:
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- bc
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- dd
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- free
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- awk
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- mkswap
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- swapon
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- swapoff
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- mkfs/ mkfs.ext4
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For more information please refer:
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kernel-source-tree/Documentation/blockdev/zram.txt
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