1IOTOP(8)                    System Manager's Manual                   IOTOP(8)
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NAME

6       iotop - simple top-like I/O monitor
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SYNOPSIS

9       iotop [OPTIONS]
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DESCRIPTION

12       iotop  watches  I/O  usage  information  output  by  the  Linux  kernel
13       (requires 2.6.20 or later) and displays a table of current I/O usage by
14       processes   or   threads   on   the   system.   At   least   the   CON‐
15       FIG_TASK_DELAY_ACCT,  CONFIG_TASK_IO_ACCOUNTING,  CONFIG_TASKSTATS  and
16       CONFIG_VM_EVENT_COUNTERS  options need to be enabled in your Linux ker‐
17       nel build configuration.
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19       iotop displays columns for the I/O bandwidth read and written  by  each
20       process/thread  during  the  sampling period. It also displays the per‐
21       centage of time the thread/process spent while swapping  in  and  while
22       waiting  on  I/O.  For  each process, its I/O priority (class/level) is
23       shown.
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25       In addition, the total I/O bandwidth read and written during  the  sam‐
26       pling period is displayed at the top of the interface.  Total DISK READ
27       and Total DISK WRITE values represent total read  and  write  bandwidth
28       between  processes  and kernel threads on the one side and kernel block
29       device subsystem on the other. While Current DISK READ and Current DISK
30       WRITE  values  represent  corresponding bandwidths for current disk I/O
31       between kernel block device subsystem  and  underlying  hardware  (HDD,
32       SSD,  etc.).   Thus  Total  and  Current values may not be equal at any
33       given moment of time due to data caching and I/O operations  reordering
34       that take place inside Linux kernel.
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36       Use  the  left and right arrows to change the sorting, r to reverse the
37       sorting order, o to toggle the --only option, p to  toggle  the  --pro‐
38       cesses  option, a to toggle the --accumulated option, q to quit or i to
39       change the priority of a thread or a process's thread(s). Any other key
40       will force a refresh.
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OPTIONS

43       -v, --version
44              Show the version number and exit
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46       -h, --help
47              Show usage information and exit
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49       -o, --only
50              Only  show  processes  or threads actually doing I/O, instead of
51              showing all processes or threads. This can be  dynamically  tog‐
52              gled by pressing o.
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54       -b, --batch
55              Turn on non-interactive mode.  Useful for logging I/O usage over
56              time.
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58       -n NUM, --iter=NUM
59              Set the number of iterations  before  quitting  (never  quit  by
60              default).  This is most useful in non-interactive mode.
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62       -d SEC, --delay=SEC
63              Set  the  delay  between  iterations  in  seconds  (1  second by
64              default).  Accepts non-integer values such as 1.1 seconds.
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66       -p PID, --pid=PID
67              A list of processes/threads to monitor (all by default).
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69       -u USER, --user=USER
70              A list of users to monitor (all by default)
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72       -P, --processes
73              Only show processes. Normally iotop shows all threads.
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75       -a, --accumulated
76              Show accumulated I/O instead of bandwidth. In this  mode,  iotop
77              shows the amount of I/O processes have done since iotop started.
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79       -k, --kilobytes
80              Use  kilobytes  instead  of  a human friendly unit. This mode is
81              useful when scripting the batch mode of iotop. Instead of choos‐
82              ing  the  most  appropriate unit iotop will display all sizes in
83              kilobytes.
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85       -t, --time
86              Add a timestamp on each line (implies --batch). Each  line  will
87              be prefixed by the current time.
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89       -c, --fullcmdline
90              Show processes' full file path & parameters.
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92       -1, --hide-pid
93              Hide PID/TID column
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95       -2, --hide-prio
96              Hide PRIO column
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98       -3, --hide-user
99              Hide USER column
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101       -4, --hide-read
102              Hide DISK READ column
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104       -5, --hide-write
105              Hide DISK WRITE column
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107       -6, --hide-swapin
108              Hide SWAPIN column
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110       -7, --hide-io
111              Hide IO column
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113       -8, --hide-graph
114              Hide GRAPH column
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116       -9, --hide-command
117              Hide COMMAND column
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119       -q, --quiet
120              Suppress some lines of header (implies --batch). This option can
121              be specified up to three times to remove header lines.
122              -q     column names are only printed on the first iteration,
123              -qq    column names are never printed,
124              -qqq   the I/O summary is never printed.
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126       -H, --no-help
127              Suppress the keyboard shortcuts help display.
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KEYBOARD SHORTCUTS

130       q, Q   Exit
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132       <space>, r, R
133              Toggle sort order
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135       <home> Sort by column PID/TID
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137       <end>  Sort by column COMMAND
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139       <right>
140              Sort by next column
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142       <left> Sort by previous column
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144       o, O   Toggle showing only processes with IO activity
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146       p, P   Toggle showing processes/threads
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148       a, A   Toggle showing accumulated/current values
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150       ?, h, H
151              Toggle showing shortcut help
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153       c, C   Toggle showing full command line
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155       1, 2, 3, 4, 5, 6, 7, 8, 9
156              Toggle showing the column  (column  number  corresponds  to  the
157              shortcut)
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159       i, I   IOnice a process/thread (depends on process/thread display mode)
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161       u, U   Toggle using Unicode/ASCII characters for pseudo graph
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SEE ALSO

164       ionice(1), top(1), vmstat(1), atop(1), htop(1)
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AUTHOR

167       The original Python iotop implementation was written by Guillaume Chaz‐
168       arain. This rewrite in C started in 2014  by  Vyacheslav  Trushkin  and
169       reworked  to  include  all features from the original Python version in
170       2020 by Boian Bonev.
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172       This manual page was started by Paul Wise for the Debian project and is
173       placed in the public domain.
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177                              September 30, 2020                      IOTOP(8)
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