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                 ==  ===================================
  10                  1  major number
  11                  2  minor mumber
  12                  3  device name
  13                  4  reads completed successfully
  14                  5  reads merged
  15                  6  sectors read
  16                  7  time spent reading (ms)
  17                  8  writes completed
  18                  9  writes merged
  19                 10  sectors written
  20                 11  time spent writing (ms)
  21                 12  I/Os currently in progress
  22                 13  time spent doing I/Os (ms)
  23                 14  weighted time spent doing I/Os (ms)
  24                 ==  ===================================
  25
  26                 Kernel 4.18+ appends four more fields for discard
  27                 tracking putting the total at 18:
  28
  29                 ==  ===================================
  30                 15  discards completed successfully
  31                 16  discards merged
  32                 17  sectors discarded
  33                 18  time spent discarding
  34                 ==  ===================================
  35
  36                 Kernel 5.5+ appends two more fields for flush requests:
  37
  38                 ==  =====================================
  39                 19  flush requests completed successfully
  40                 20  time spent flushing
  41                 ==  =====================================
  42
  43                 For more details refer to Documentation/admin-guide/iostats.rst