Documentation/ABI/testing/procfs-diskstats

   1 What:           /proc/diskstats
   2 Date:           February 2008
   3 Contact:        Jerome Marchand <jmarchan@redhat.com>
   4 Description:
   5                 The /proc/diskstats file displays the I/O statistics
   6                 of block devices. Each line contains the following 14
   7                 fields:
   8
   9                  1 - major number
  10                  2 - minor mumber
  11                  3 - device name
  12                  4 - reads completed successfully
  13                  5 - reads merged
  14                  6 - sectors read
  15                  7 - time spent reading (ms)
  16                  8 - writes completed
  17                  9 - writes merged
  18                 10 - sectors written
  19                 11 - time spent writing (ms)
  20                 12 - I/Os currently in progress
  21                 13 - time spent doing I/Os (ms)
  22                 14 - weighted time spent doing I/Os (ms)
  23
  24                 Kernel 4.18+ appends four more fields for discard
  25                 tracking putting the total at 18:
  26
  27                 15 - discards completed successfully
  28                 16 - discards merged
  29                 17 - sectors discarded
  30                 18 - time spent discarding
  31
  32                 Kernel 5.5+ appends two more fields for flush requests:
  33
  34                 19 - flush requests completed successfully
  35                 20 - time spent flushing
  36
  37                 For more details refer to Documentation/admin-guide/iostats.rst