1What: /sys/block/zram<id>/disksize 2Date: August 2010 3Contact: Nitin Gupta <ngupta@vflare.org> 4Description: 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 10What: /sys/block/zram<id>/initstate 11Date: August 2010 12Contact: Nitin Gupta <ngupta@vflare.org> 13Description: 14 The initstate file is read-only and shows the initialization 15 state of the device. 16 17What: /sys/block/zram<id>/reset 18Date: August 2010 19Contact: Nitin Gupta <ngupta@vflare.org> 20Description: 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 25What: /sys/block/zram<id>/comp_algorithm 26Date: February 2014 27Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 28Description: 29 The comp_algorithm file is read-write and lets to show 30 available and selected compression algorithms, change 31 compression algorithm selection. 32 33What: /sys/block/zram<id>/mem_used_max 34Date: August 2014 35Contact: Minchan Kim <minchan@kernel.org> 36Description: 37 The mem_used_max file is write-only and is used to reset 38 the counter of maximum memory zram have consumed to store 39 compressed data. For resetting the value, you should write 40 "0". Otherwise, you could see -EINVAL. 41 Unit: bytes 42 43What: /sys/block/zram<id>/mem_limit 44Date: August 2014 45Contact: Minchan Kim <minchan@kernel.org> 46Description: 47 The mem_limit file is write-only and specifies the maximum 48 amount of memory ZRAM can use to store the compressed data. 49 The limit could be changed in run time and "0" means disable 50 the limit. No limit is the initial state. Unit: bytes 51 52What: /sys/block/zram<id>/compact 53Date: August 2015 54Contact: Minchan Kim <minchan@kernel.org> 55Description: 56 The compact file is write-only and trigger compaction for 57 allocator zrm uses. The allocator moves some objects so that 58 it could free fragment space. 59 60What: /sys/block/zram<id>/io_stat 61Date: August 2015 62Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 63Description: 64 The io_stat file is read-only and accumulates device's I/O 65 statistics not accounted by block layer. For example, 66 failed_reads, failed_writes, etc. File format is similar to 67 block layer statistics file format. 68 69What: /sys/block/zram<id>/mm_stat 70Date: August 2015 71Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 72Description: 73 The mm_stat file is read-only and represents device's mm 74 statistics (orig_data_size, compr_data_size, etc.) in a format 75 similar to block layer statistics file format. 76 77What: /sys/block/zram<id>/debug_stat 78Date: July 2016 79Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 80Description: 81 The debug_stat file is read-only and represents various 82 device's debugging info useful for kernel developers. Its 83 format is not documented intentionally and may change 84 anytime without any notice. 85 86What: /sys/block/zram<id>/backing_dev 87Date: June 2017 88Contact: Minchan Kim <minchan@kernel.org> 89Description: 90 The backing_dev file is read-write and set up backing 91 device for zram to write incompressible pages. 92 For using, user should enable CONFIG_ZRAM_WRITEBACK. 93 94What: /sys/block/zram<id>/idle 95Date: November 2018 96Contact: Minchan Kim <minchan@kernel.org> 97Description: 98 idle file is write-only and mark zram slot as idle. 99 If system has mounted debugfs, user can see which slots 100 are idle via /sys/kernel/debug/zram/zram<id>/block_state 101 102What: /sys/block/zram<id>/writeback 103Date: November 2018 104Contact: Minchan Kim <minchan@kernel.org> 105Description: 106 The writeback file is write-only and trigger idle and/or 107 huge page writeback to backing device. 108 109What: /sys/block/zram<id>/bd_stat 110Date: November 2018 111Contact: Minchan Kim <minchan@kernel.org> 112Description: 113 The bd_stat file is read-only and represents backing device's 114 statistics (bd_count, bd_reads, bd_writes) in a format 115 similar to block layer statistics file format. 116 117What: /sys/block/zram<id>/writeback_limit_enable 118Date: November 2018 119Contact: Minchan Kim <minchan@kernel.org> 120Description: 121 The writeback_limit_enable file is read-write and specifies 122 eanbe of writeback_limit feature. "1" means eable the feature. 123 No limit "0" is the initial state. 124 125What: /sys/block/zram<id>/writeback_limit 126Date: November 2018 127Contact: Minchan Kim <minchan@kernel.org> 128Description: 129 The writeback_limit file is read-write and specifies the maximum 130 amount of writeback ZRAM can do. The limit could be changed 131 in run time. 132 133What: /sys/block/zram<id>/recomp_algorithm 134Date: November 2022 135Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 136Description: 137 The recomp_algorithm file is read-write and allows to set 138 or show secondary compression algorithms. 139 140What: /sys/block/zram<id>/recompress 141Date: November 2022 142Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 143Description: 144 The recompress file is write-only and triggers re-compression 145 with secondary compression algorithms. 146 147What: /sys/block/zram<id>/algorithm_params 148Date: August 2024 149Contact: Sergey Senozhatsky <senozhatsky@chromium.org> 150Description: 151 The algorithm_params file is write-only and is used to setup 152 compression algorithm parameters. 153