1fatrace(1) General Commands Manual fatrace(1)
2
3
4
6 fatrace - report system wide file access events
7
8
10 fatrace [ OPTIONS ]
11
12
14 fatrace reports file access events from all running processes.
15
16 It does not report file access by fatrace itself, to avoid logging
17 events caused by writing the output into a file. It also ignores events
18 on virtual and kernel file systems such as sysfs, proc, and devtmpfs.
19
20 Its main purpose is to find processes which keep waking up the disk
21 unnecessarily and thus prevent some power saving.
22
23 By default, events are reported to stdout. This will cause some loops
24 if you run this tool in e. g. gnome-terminal, as this causes a disk
25 access for every output line. To avoid this, redirect the output into a
26 file.
27
28
30 A typical event looks like
31
32 rsyslogd(875): W /var/log/auth.log
33 compiz(1971): O device 8:2 inode 658203
34
35 The line has the following fields:
36
37
38 · Process name. This is read from /proc/pid/comm, and might be abbrevi‐
39 ated for long process names.
40
41
42 · Process ID
43
44
45 · Event type: Open, Read, Write, Close. Events on directories are +
46 (create), Delete, < (moved from), or > (moved to). Combinations are
47 possible, such as CW for closing a written file, or <> for renaming a
48 file within the same directory.
49
50 Directory events can only be detected on Linux 5.1 or higher.
51
52
53 · Affected file. In some cases the path and name cannot be determined,
54 e. g. because it is a temporary file which is already deleted. In
55 that case, it prints the devices' major and minor number and the
56 inode number. To examine such a process in more detail, you should
57 consider using strace(1).
58
59 If you specify the --timestamp option, the first field will be the cur‐
60 rent time.
61
62
64 -c, --current-mount
65 Only record events on partition/mount of current directory.
66 Without this option, all (real) partitions/mount points are
67 being watched.
68
69
70 -o FILE, --output=FILE
71 Write events to given file instead of standard output.
72
73
74 -s SECONDS, --seconds=SECONDS
75 Stop after the given number of seconds.
76
77
78 -t, --timestamp
79 Add timestamp to events. When this option is given once, the
80 format will be a human readable hour:minute:second.microsecond;
81 when given twice, the timestamp is printed as seconds/microsec‐
82 onds since the epoch.
83
84
85 -p PID, --ignore-pid=PID
86 Ignore events for this process ID. Can be specified multiple
87 times.
88
89
90 -f TYPES, --filter=TYPES
91 Show only the given event types. TYPES is a list of C, R, O, W,
92 D, +, or < with the above meanings. < and > both mean "move" and
93 will always enable both directions.
94
95 E. g. use --filter=OC to only show open and close events.
96
97
98 -C COMMAND, --command=COMMAND
99 Show only events for this command.
100
101
102 -h , --help
103 Print help and exit.
104
105
107 fatrace is developed by Martin Pitt <martin.pitt@ubuntu.com>.
108
109
110
111
112Martin Pitt February 07, 2012 fatrace(1)