xref: /linux/Documentation/ABI/testing/procfs-diskstats (revision a940daa52167e9db8ecce82213813b735a9d9f23)
1What:		/proc/diskstats
2Date:		February 2008
3Contact:	Jerome Marchand <jmarchan@redhat.com>
4Description:
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 number
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
44