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>/max_comp_streams 26Date: February 2014 27Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 28Description: 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 33What: /sys/block/zram<id>/comp_algorithm 34Date: February 2014 35Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 36Description: 37 The comp_algorithm file is read-write and lets to show 38 available and selected compression algorithms, change 39 compression algorithm selection. 40 41What: /sys/block/zram<id>/mem_used_max 42Date: August 2014 43Contact: Minchan Kim <minchan@kernel.org> 44Description: 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 51What: /sys/block/zram<id>/mem_limit 52Date: August 2014 53Contact: Minchan Kim <minchan@kernel.org> 54Description: 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 60What: /sys/block/zram<id>/compact 61Date: August 2015 62Contact: Minchan Kim <minchan@kernel.org> 63Description: 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 68What: /sys/block/zram<id>/io_stat 69Date: August 2015 70Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 71Description: 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 77What: /sys/block/zram<id>/mm_stat 78Date: August 2015 79Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 80Description: 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 85What: /sys/block/zram<id>/debug_stat 86Date: July 2016 87Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> 88Description: 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 94What: /sys/block/zram<id>/backing_dev 95Date: June 2017 96Contact: Minchan Kim <minchan@kernel.org> 97Description: 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 102What: /sys/block/zram<id>/idle 103Date: November 2018 104Contact: Minchan Kim <minchan@kernel.org> 105Description: 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 110What: /sys/block/zram<id>/writeback 111Date: November 2018 112Contact: Minchan Kim <minchan@kernel.org> 113Description: 114 The writeback file is write-only and trigger idle and/or 115 huge page writeback to backing device. 116 117What: /sys/block/zram<id>/bd_stat 118Date: November 2018 119Contact: Minchan Kim <minchan@kernel.org> 120Description: 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 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 and "0" means disable the limit. 132 No limit is the initial state. 133