1 What: /sys/block/zram<id>/disksize 2 Date: August 2010 3 Contact: Nitin Gupta <ngupta@vflare.org> 4 Description: 5 The disksize file is read-write and specifies the disk size 6 which represents the limit on the *uncompressed* worth of data 7 that can be stored in this disk. 8 Unit: bytes 9 10 What: /sys/block/zram<id>/initstate 11 Date: August 2010 12 Contact: Nitin Gupta <ngupta@vflare.org> 13 Description: 14 The initstate file is read-only and shows the initialization 15 state of the device. 16 17 What: /sys/block/zram<id>/reset 18 Date: August 2010 19 Contact: Nitin Gupta <ngupta@vflare.org> 20 Description: 21 The reset file is write-only and allows resetting the 22 device. The reset operation frees all the memory associated 23 with this device. 24 25 What: /sys/block/zram<id>/max_comp_streams 26 Date: February 2014 27 Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 28 Description: 29 The max_comp_streams file is read-write and specifies the 30 number of backend's zcomp_strm compression streams (number of 31 concurrent compress operations). 32 33 What: /sys/block/zram<id>/comp_algorithm 34 Date: February 2014 35 Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 36 Description: 37 The comp_algorithm file is read-write and lets to show 38 available and selected compression algorithms, change 39 compression algorithm selection. 40 41 What: /sys/block/zram<id>/mem_used_max 42 Date: August 2014 43 Contact: Minchan Kim <minchan@kernel.org> 44 Description: 45 The mem_used_max file is write-only and is used to reset 46 the counter of maximum memory zram have consumed to store 47 compressed data. For resetting the value, you should write 48 "0". Otherwise, you could see -EINVAL. 49 Unit: bytes 50 51 What: /sys/block/zram<id>/mem_limit 52 Date: August 2014 53 Contact: Minchan Kim <minchan@kernel.org> 54 Description: 55 The mem_limit file is write-only and specifies the maximum 56 amount of memory ZRAM can use to store the compressed data. 57 The limit could be changed in run time and "0" means disable 58 the limit. No limit is the initial state. Unit: bytes 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 and trigger compaction for 65 allocator zrm uses. The allocator moves some objects so that 66 it could free fragment space. 67 68 What: /sys/block/zram<id>/io_stat 69 Date: August 2015 70 Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 71 Description: 72 The io_stat file is read-only and accumulates device's I/O 73 statistics not accounted by block layer. For example, 74 failed_reads, failed_writes, etc. File format is similar to 75 block layer statistics file format. 76 77 What: /sys/block/zram<id>/mm_stat 78 Date: August 2015 79 Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 80 Description: 81 The mm_stat file is read-only and represents device's mm 82 statistics (orig_data_size, compr_data_size, etc.) in a format 83 similar to block layer statistics file format. 84 85 What: /sys/block/zram<id>/debug_stat 86 Date: July 2016 87 Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 88 Description: 89 The debug_stat file is read-only and represents various 90 device's debugging info useful for kernel developers. Its 91 format is not documented intentionally and may change 92 anytime without any notice. 93 94 What: /sys/block/zram<id>/backing_dev 95 Date: June 2017 96 Contact: Minchan Kim <minchan@kernel.org> 97 Description: 98 The backing_dev file is read-write and set up backing 99 device for zram to write incompressible pages. 100 For using, user should enable CONFIG_ZRAM_WRITEBACK. 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 mark zram slot as idle. 107 If system has mounted debugfs, user can see which slots 108 are idle via /sys/kernel/debug/zram/zram<id>/block_state 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-only and trigger idle and/or 115 huge page writeback to backing device. 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 and represents backing device's 122 statistics (bd_count, bd_reads, bd_writes) in a format 123 similar to block layer statistics file format. 124 125 What: /sys/block/zram<id>/writeback_limit_enable 126 Date: November 2018 127 Contact: Minchan Kim <minchan@kernel.org> 128 Description: 129 The writeback_limit_enable file is read-write and specifies 130 eanbe of writeback_limit feature. "1" means eable the feature. 131 No limit "0" is the initial state. 132 133 What: /sys/block/zram<id>/writeback_limit 134 Date: November 2018 135 Contact: Minchan Kim <minchan@kernel.org> 136 Description: 137 The writeback_limit file is read-write and specifies the maximum 138 amount of writeback ZRAM can do. The limit could be changed 139 in run time. 140 141 What: /sys/block/zram<id>/recomp_algorithm 142 Date: November 2022 143 Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 144 Description: 145 The recomp_algorithm file is read-write and allows to set 146 or show secondary compression algorithms. 147 148 What: /sys/block/zram<id>/recompress 149 Date: November 2022 150 Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 151 Description: 152 The recompress file is write-only and triggers re-compression 153 with secondary compression algorithms. 154 155 What: /sys/block/zram<id>/algorithm_params 156 Date: August 2024 157 Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 158 Description: 159 The algorithm_params file is write-only and is used to setup 160 compression algorithm parameters. 161