1What:		/sys/block/zram<id>/num_reads
2Date:		August 2015
3Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
4Description:
5		The num_reads file is read-only and specifies the number of
6		reads (failed or successful) done on this device.
7		Now accessible via zram<id>/stat node.
8
9What:		/sys/block/zram<id>/num_writes
10Date:		August 2015
11Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
12Description:
13		The num_writes file is read-only and specifies the number of
14		writes (failed or successful) done on this device.
15		Now accessible via zram<id>/stat node.
16
17What:		/sys/block/zram<id>/invalid_io
18Date:		August 2015
19Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
20Description:
21		The invalid_io file is read-only and specifies the number of
22		non-page-size-aligned I/O requests issued to this device.
23		Now accessible via zram<id>/io_stat node.
24
25What:		/sys/block/zram<id>/failed_reads
26Date:		August 2015
27Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
28Description:
29		The failed_reads file is read-only and specifies the number of
30		failed reads happened on this device.
31		Now accessible via zram<id>/io_stat node.
32
33What:		/sys/block/zram<id>/failed_writes
34Date:		August 2015
35Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
36Description:
37		The failed_writes file is read-only and specifies the number of
38		failed writes happened on this device.
39		Now accessible via zram<id>/io_stat node.
40
41What:		/sys/block/zram<id>/notify_free
42Date:		August 2015
43Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
44Description:
45		The notify_free file is read-only. Depending on device usage
46		scenario it may account a) the number of pages freed because
47		of swap slot free notifications or b) the number of pages freed
48		because of REQ_DISCARD requests sent by bio. The former ones
49		are sent to a swap block device when a swap slot is freed, which
50		implies that this disk is being used as a swap disk. The latter
51		ones are sent by filesystem mounted with discard option,
52		whenever some data blocks are getting discarded.
53		Now accessible via zram<id>/io_stat node.
54
55What:		/sys/block/zram<id>/zero_pages
56Date:		August 2015
57Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
58Description:
59		The zero_pages file is read-only and specifies number of zero
60		filled pages written to this disk. No memory is allocated for
61		such pages.
62		Now accessible via zram<id>/mm_stat node.
63
64What:		/sys/block/zram<id>/orig_data_size
65Date:		August 2015
66Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
67Description:
68		The orig_data_size file is read-only and specifies uncompressed
69		size of data stored in this disk. This excludes zero-filled
70		pages (zero_pages) since no memory is allocated for them.
71		Unit: bytes
72		Now accessible via zram<id>/mm_stat node.
73
74What:		/sys/block/zram<id>/compr_data_size
75Date:		August 2015
76Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
77Description:
78		The compr_data_size file is read-only and specifies compressed
79		size of data stored in this disk. So, compression ratio can be
80		calculated using orig_data_size and this statistic.
81		Unit: bytes
82		Now accessible via zram<id>/mm_stat node.
83
84What:		/sys/block/zram<id>/mem_used_total
85Date:		August 2015
86Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
87Description:
88		The mem_used_total file is read-only and specifies the amount
89		of memory, including allocator fragmentation and metadata
90		overhead, allocated for this disk. So, allocator space
91		efficiency can be calculated using compr_data_size and this
92		statistic.
93		Unit: bytes
94		Now accessible via zram<id>/mm_stat node.
95
96What:		/sys/block/zram<id>/mem_used_max
97Date:		August 2015
98Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
99Description:
100		The mem_used_max file is read/write and specifies the amount
101		of maximum memory zram have consumed to store compressed data.
102		For resetting the value, you should write "0". Otherwise,
103		you could see -EINVAL.
104		Unit: bytes
105		Downgraded to write-only node: so it's possible to set new
106		value only; its current value is stored in zram<id>/mm_stat
107		node.
108
109What:		/sys/block/zram<id>/mem_limit
110Date:		August 2015
111Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
112Description:
113		The mem_limit file is read/write and specifies the maximum
114		amount of memory ZRAM can use to store the compressed data.
115		The limit could be changed in run time and "0" means disable
116		the limit.  No limit is the initial state.  Unit: bytes
117		Downgraded to write-only node: so it's possible to set new
118		value only; its current value is stored in zram<id>/mm_stat
119		node.
120