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+What: /sys/block/zram<id>/disksize
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The disksize file is read-write and specifies the disk size
+ which represents the limit on the *uncompressed* worth of data
+ that can be stored in this disk.
+ Unit: bytes
+
+What: /sys/block/zram<id>/initstate
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The initstate file is read-only and shows the initialization
+ state of the device.
+
+What: /sys/block/zram<id>/reset
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The reset file is write-only and allows resetting the
+ device. The reset operation frees all the memory associated
+ with this device.
+
+What: /sys/block/zram<id>/num_reads
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The num_reads file is read-only and specifies the number of
+ reads (failed or successful) done on this device.
+
+What: /sys/block/zram<id>/num_writes
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The num_writes file is read-only and specifies the number of
+ writes (failed or successful) done on this device.
+
+What: /sys/block/zram<id>/invalid_io
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The invalid_io file is read-only and specifies the number of
+ non-page-size-aligned I/O requests issued to this device.
+
+What: /sys/block/zram<id>/failed_reads
+Date: February 2014
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The failed_reads file is read-only and specifies the number of
+ failed reads happened on this device.
+
+What: /sys/block/zram<id>/failed_writes
+Date: February 2014
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The failed_writes file is read-only and specifies the number of
+ failed writes happened on this device.
+
+What: /sys/block/zram<id>/max_comp_streams
+Date: February 2014
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The max_comp_streams file is read-write and specifies the
+ number of backend's zcomp_strm compression streams (number of
+ concurrent compress operations).
+
+What: /sys/block/zram<id>/comp_algorithm
+Date: February 2014
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The comp_algorithm file is read-write and lets to show
+ available and selected compression algorithms, change
+ compression algorithm selection.
+
+What: /sys/block/zram<id>/notify_free
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The notify_free file is read-only. Depending on device usage
+ scenario it may account a) the number of pages freed because
+ of swap slot free notifications or b) the number of pages freed
+ because of REQ_DISCARD requests sent by bio. The former ones
+ are sent to a swap block device when a swap slot is freed, which
+ implies that this disk is being used as a swap disk. The latter
+ ones are sent by filesystem mounted with discard option,
+ whenever some data blocks are getting discarded.
+
+What: /sys/block/zram<id>/zero_pages
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The zero_pages file is read-only and specifies number of zero
+ filled pages written to this disk. No memory is allocated for
+ such pages.
+
+What: /sys/block/zram<id>/orig_data_size
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The orig_data_size file is read-only and specifies uncompressed
+ size of data stored in this disk. This excludes zero-filled
+ pages (zero_pages) since no memory is allocated for them.
+ Unit: bytes
+
+What: /sys/block/zram<id>/compr_data_size
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The compr_data_size file is read-only and specifies compressed
+ size of data stored in this disk. So, compression ratio can be
+ calculated using orig_data_size and this statistic.
+ Unit: bytes
+
+What: /sys/block/zram<id>/mem_used_total
+Date: August 2010
+Contact: Nitin Gupta <ngupta@vflare.org>
+Description:
+ The mem_used_total file is read-only and specifies the amount
+ of memory, including allocator fragmentation and metadata
+ overhead, allocated for this disk. So, allocator space
+ efficiency can be calculated using compr_data_size and this
+ statistic.
+ Unit: bytes
+
+What: /sys/block/zram<id>/mem_used_max
+Date: August 2014
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The mem_used_max file is read/write and specifies the amount
+ of maximum memory zram have consumed to store compressed data.
+ For resetting the value, you should write "0". Otherwise,
+ you could see -EINVAL.
+ Unit: bytes
+
+What: /sys/block/zram<id>/mem_limit
+Date: August 2014
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The mem_limit file is read/write and specifies the maximum
+ amount of memory ZRAM can use to store the compressed data. The
+ limit could be changed in run time and "0" means disable the
+ limit. No limit is the initial state. Unit: bytes
+
+What: /sys/block/zram<id>/compact
+Date: August 2015
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The compact file is write-only and trigger compaction for
+ allocator zrm uses. The allocator moves some objects so that
+ it could free fragment space.
+
+What: /sys/block/zram<id>/io_stat
+Date: August 2015
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The io_stat file is read-only and accumulates device's I/O
+ statistics not accounted by block layer. For example,
+ failed_reads, failed_writes, etc. File format is similar to
+ block layer statistics file format.
+
+What: /sys/block/zram<id>/mm_stat
+Date: August 2015
+Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+ The mm_stat file is read-only and represents device's mm
+ statistics (orig_data_size, compr_data_size, etc.) in a format
+ similar to block layer statistics file format.