1 What: /sys/block/zram<id>/disksize 1 What: /sys/block/zram<id>/disksize
2 Date: August 2010 2 Date: August 2010
3 Contact: Nitin Gupta <ngupta@vflare.org> 3 Contact: Nitin Gupta <ngupta@vflare.org>
4 Description: 4 Description:
5 The disksize file is read-writ 5 The disksize file is read-write and specifies the disk size
6 which represents the limit on 6 which represents the limit on the *uncompressed* worth of data
7 that can be stored in this dis 7 that can be stored in this disk.
8 Unit: bytes <<
9 8
10 What: /sys/block/zram<id>/initstate 9 What: /sys/block/zram<id>/initstate
11 Date: August 2010 10 Date: August 2010
12 Contact: Nitin Gupta <ngupta@vflare.org> 11 Contact: Nitin Gupta <ngupta@vflare.org>
13 Description: 12 Description:
14 The initstate file is read-onl !! 13 The disksize file is read-only and shows the initialization
15 state of the device. 14 state of the device.
16 15
17 What: /sys/block/zram<id>/reset 16 What: /sys/block/zram<id>/reset
18 Date: August 2010 17 Date: August 2010
19 Contact: Nitin Gupta <ngupta@vflare.org> 18 Contact: Nitin Gupta <ngupta@vflare.org>
20 Description: 19 Description:
21 The reset file is write-only a !! 20 The disksize file is write-only and allows resetting the
22 device. The reset operation fr !! 21 device. The reset operation frees all the memory assocaited
23 with this device. 22 with this device.
24 23
25 What: /sys/block/zram<id>/max_comp_s !! 24 What: /sys/block/zram<id>/num_reads
26 Date: February 2014 !! 25 Date: August 2010
27 Contact: Sergey Senozhatsky <sergey.seno !! 26 Contact: Nitin Gupta <ngupta@vflare.org>
28 Description: !! 27 Description:
29 The max_comp_streams file is r !! 28 The num_reads file is read-only and specifies the number of
30 number of backend's zcomp_strm !! 29 reads (failed or successful) done on this device.
31 concurrent compress operations !! 30
32 !! 31 What: /sys/block/zram<id>/num_writes
33 What: /sys/block/zram<id>/comp_algor !! 32 Date: August 2010
34 Date: February 2014 !! 33 Contact: Nitin Gupta <ngupta@vflare.org>
35 Contact: Sergey Senozhatsky <sergey.seno !! 34 Description:
36 Description: !! 35 The num_writes file is read-only and specifies the number of
37 The comp_algorithm file is rea !! 36 writes (failed or successful) done on this device.
38 available and selected compres !! 37
39 compression algorithm selectio !! 38 What: /sys/block/zram<id>/invalid_io
40 !! 39 Date: August 2010
41 What: /sys/block/zram<id>/mem_used_m !! 40 Contact: Nitin Gupta <ngupta@vflare.org>
42 Date: August 2014 !! 41 Description:
43 Contact: Minchan Kim <minchan@kernel.org !! 42 The invalid_io file is read-only and specifies the number of
44 Description: !! 43 non-page-size-aligned I/O requests issued to this device.
45 The mem_used_max file is write !! 44
46 the counter of maximum memory !! 45 What: /sys/block/zram<id>/notify_free
47 compressed data. For resetting !! 46 Date: August 2010
48 "0". Otherwise, you could see !! 47 Contact: Nitin Gupta <ngupta@vflare.org>
>> 48 Description:
>> 49 The notify_free file is read-only and specifies the number of
>> 50 swap slot free notifications received by this device. These
>> 51 notifications are send to a swap block device when a swap slot
>> 52 is freed. This statistic is applicable only when this disk is
>> 53 being used as a swap disk.
>> 54
>> 55 What: /sys/block/zram<id>/discard
>> 56 Date: August 2010
>> 57 Contact: Nitin Gupta <ngupta@vflare.org>
>> 58 Description:
>> 59 The discard file is read-only and specifies the number of
>> 60 discard requests received by this device. These requests
>> 61 provide information to block device regarding blocks which are
>> 62 no longer used by filesystem.
>> 63
>> 64 What: /sys/block/zram<id>/zero_pages
>> 65 Date: August 2010
>> 66 Contact: Nitin Gupta <ngupta@vflare.org>
>> 67 Description:
>> 68 The zero_pages file is read-only and specifies number of zero
>> 69 filled pages written to this disk. No memory is allocated for
>> 70 such pages.
>> 71
>> 72 What: /sys/block/zram<id>/orig_data_size
>> 73 Date: August 2010
>> 74 Contact: Nitin Gupta <ngupta@vflare.org>
>> 75 Description:
>> 76 The orig_data_size file is read-only and specifies uncompressed
>> 77 size of data stored in this disk. This excludes zero-filled
>> 78 pages (zero_pages) since no memory is allocated for them.
>> 79 Unit: bytes
>> 80
>> 81 What: /sys/block/zram<id>/compr_data_size
>> 82 Date: August 2010
>> 83 Contact: Nitin Gupta <ngupta@vflare.org>
>> 84 Description:
>> 85 The compr_data_size file is read-only and specifies compressed
>> 86 size of data stored in this disk. So, compression ratio can be
>> 87 calculated using orig_data_size and this statistic.
49 Unit: bytes 88 Unit: bytes
50 89
51 What: /sys/block/zram<id>/mem_limit !! 90 What: /sys/block/zram<id>/mem_used_total
52 Date: August 2014 !! 91 Date: August 2010
53 Contact: Minchan Kim <minchan@kernel.org !! 92 Contact: Nitin Gupta <ngupta@vflare.org>
54 Description: <<
55 The mem_limit file is write-on <<
56 amount of memory ZRAM can use <<
57 The limit could be changed in <<
58 the limit. No limit is the ini <<
59 <<
60 What: /sys/block/zram<id>/compact <<
61 Date: August 2015 <<
62 Contact: Minchan Kim <minchan@kernel.org <<
63 Description: <<
64 The compact file is write-only <<
65 allocator zrm uses. The alloca <<
66 it could free fragment space. <<
67 <<
68 What: /sys/block/zram<id>/io_stat <<
69 Date: August 2015 <<
70 Contact: Sergey Senozhatsky <sergey.seno <<
71 Description: <<
72 The io_stat file is read-only <<
73 statistics not accounted by bl <<
74 failed_reads, failed_writes, e <<
75 block layer statistics file fo <<
76 <<
77 What: /sys/block/zram<id>/mm_stat <<
78 Date: August 2015 <<
79 Contact: Sergey Senozhatsky <sergey.seno <<
80 Description: <<
81 The mm_stat file is read-only <<
82 statistics (orig_data_size, co <<
83 similar to block layer statist <<
84 <<
85 What: /sys/block/zram<id>/debug_stat <<
86 Date: July 2016 <<
87 Contact: Sergey Senozhatsky <sergey.seno <<
88 Description: <<
89 The debug_stat file is read-on <<
90 device's debugging info useful <<
91 format is not documented inten <<
92 anytime without any notice. <<
93 <<
94 What: /sys/block/zram<id>/backing_de <<
95 Date: June 2017 <<
96 Contact: Minchan Kim <minchan@kernel.org <<
97 Description: <<
98 The backing_dev file is read-w <<
99 device for zram to write incom <<
100 For using, user should enable <<
101 <<
102 What: /sys/block/zram<id>/idle <<
103 Date: November 2018 <<
104 Contact: Minchan Kim <minchan@kernel.org <<
105 Description: <<
106 idle file is write-only and ma <<
107 If system has mounted debugfs, <<
108 are idle via /sys/kernel/debug <<
109 <<
110 What: /sys/block/zram<id>/writeback <<
111 Date: November 2018 <<
112 Contact: Minchan Kim <minchan@kernel.org <<
113 Description: <<
114 The writeback file is write-on <<
115 huge page writeback to backing <<
116 <<
117 What: /sys/block/zram<id>/bd_stat <<
118 Date: November 2018 <<
119 Contact: Minchan Kim <minchan@kernel.org <<
120 Description: <<
121 The bd_stat file is read-only <<
122 statistics (bd_count, bd_reads <<
123 similar to block layer statist <<
124 <<
125 What: /sys/block/zram<id>/writeback_ <<
126 Date: November 2018 <<
127 Contact: Minchan Kim <minchan@kernel.org <<
128 Description: <<
129 The writeback_limit_enable fil <<
130 eanbe of writeback_limit featu <<
131 No limit "0" is the initial st <<
132 <<
133 What: /sys/block/zram<id>/writeback_ <<
134 Date: November 2018 <<
135 Contact: Minchan Kim <minchan@kernel.org <<
136 Description: <<
137 The writeback_limit file is re <<
138 amount of writeback ZRAM can d <<
139 in run time. <<
140 <<
141 What: /sys/block/zram<id>/recomp_alg <<
142 Date: November 2022 <<
143 Contact: Sergey Senozhatsky <senozhatsky <<
144 Description: <<
145 The recomp_algorithm file is r <<
146 or show secondary compression <<
147 <<
148 What: /sys/block/zram<id>/recompress <<
149 Date: November 2022 <<
150 Contact: Sergey Senozhatsky <senozhatsky <<
151 Description: <<
152 The recompress file is write-o <<
153 with secondary compression alg <<
154 <<
155 What: /sys/block/zram<id>/algorithm_ <<
156 Date: August 2024 <<
157 Contact: Sergey Senozhatsky <senozhatsky <<
158 Description: 93 Description:
159 The algorithm_params file is w !! 94 The mem_used_total file is read-only and specifies the amount
160 compression algorithm paramete !! 95 of memory, including allocator fragmentation and metadata
>> 96 overhead, allocated for this disk. So, allocator space
>> 97 efficiency can be calculated using compr_data_size and this
>> 98 statistic.
>> 99 Unit: bytes
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