IOTOP(8)

🌸 NAME 🌸

iotop(8) — from the System Manager's Manual — is the simple top-like I/O monitor. 💖

✨ SYNOPSIS ✨

iotop [OPTIONS]

💖 DESCRIPTION 💖

Okay so iotop watches I/O usage information available in the Linux kernel (requires 2.6.20 or later) and displays a table of current I/O usage by processes or threads on the system. At least the CONFIG_TASK_DELAY_ACCT, CONFIG_TASK_IO_ACCOUNTING, CONFIG_TASKSTATS and CONFIG_VM_EVENT_COUNTERS options need to be enabled in your Linux kernel build configuration. 💅

Running iotop as non-root user is possible by adding the NET_ADMIN capability. This can be done by e.g.:

$ sudo setcap 'cap_net_admin+eip' <path-to>/iotop

Be warned that this will also allow other users to run it and get access to information that normally should not be available to them. 😭 Like, vibe check before you setcap, bestie.

iotop displays columns for the I/O bandwidth read and written by each process/thread during the sampling period. It also displays the percentage of time the thread/process spent while swapping in and while waiting on I/O. For each process, its I/O priority (class/level) is shown. 👑

In addition, the total I/O bandwidth read and written during the sampling period are displayed at the top of the interface. Total DISK READ and Total DISK WRITE values represent total read and write bandwidth between processes and kernel threads on one side and kernel block device subsystem on the other. While Current DISK READ and Current DISK WRITE values represent corresponding bandwidths for current disk I/O between the kernel block device subsystem and the underlying hardware (HDD, SSD, etc.). Thus Total and Current values may not be equal at any given moment of time due to data caching and I/O operations reordering that take place inside the Linux kernel. ✨

Use the left and right arrows to select the sort column, r or space to reverse the sorting order, o to toggle the --only option (this uses the visible values from the GRAPH column or the IO column in case the GRAPH column is hidden), p to toggle the --processes option, a to cycle between the --accumulated, --accum-bw and normal operation, i to change the priority of a thread or a process's thread, f to change filtering by UID/PID (--user and --pid options), 1-9 to toggle the visibility of the respective column, 0 to show all columns, up/down arrows, page-up/page-down/home/end keys to scroll and q to quit. Any unrecognized key will be ignored. 🎀

All processes or threads that have exited are displayed grayed for the same time as is visible in the GRAPH column or 3 seconds when it is hidden. The invalid data points in the GRAPHS column are displayed inverse or with letter x (see option --dead-x and x shortcut). When using unicode characters each position contains two datapoints and only the positions with two invalid data points are reversed. 🙈

It is possible for threads of a process to have different priority from their main process. This is shown with ! in the PRIO column of the main process as e.g. !be/4. 💅

Threads activity is always aggregated with and shown inside the main process. 🫶

When showing threads, they always appear below their main process and are sorted in the same way as the processes. 🌈

There are two ways to change the IO priority of a process or thread - press i and use arrows to select the process or thread from the visible ones on screen or press i and type its TID (PID and TID have the same value for the main process). Then use tab and arrows to change the priority value and confirm with enter. Shortcuts esc or q will cancel this mode. 👑

To change the UID and PID filters, press f and use tab to select the UID or PID field, then type the numerical id or n to remove the filter and confirm with enter. Filtering is always done by TID because it is unique. Note that for the main process PID is the same as TID. Shortcuts esc or q will cancel this mode. 🔥

Starting with Linux kernel 5.14.x task_delayacct is configurable at runtime and set to off by default. This setting can be changed in interactive mode by the Ctrl-T shortcut. In batch mode a warning is printed when the setting is OFF. From the command line this can be enabled by:

$ sudo sysctl kernel.task_delayacct=1

and disabled again by:

$ sudo sysctl kernel.task_delayacct=0

It is advisable to keep this option off when not using this or another monitoring program because when enabled it has some effect on system performance. ⭐

🎀 OPTIONS 🎀

• -v, --version — Show the version number and exit ✨
• -h, --help — Show usage information and exit 🫶
• -H, --help-type=TYPE — Set the type of interactive help shown. Accepted values for TYPE are none, win and inline. 👑
• -o, --only — Only show processes or threads actually doing I/O, instead of showing all processes or threads. This can be dynamically toggled by pressing o 💅
• --no-only — Show all processes or threads
• -b, --batch — Turn on non-interactive mode. Useful for logging I/O usage over time 🌙
• -n NUM, --iter=NUM — Set the number of iterations before quitting (never quit by default). This is most useful in non-interactive mode 🔁
• -d SEC, --delay=SEC — Set the delay between iterations in seconds (1 second by default). Accepts non-integer values such as 1.1 seconds ⏱️
• -p PID, --pid=PID — A process/thread id to monitor (all by default) 🎯
• -u USER, --user=USER — A user id to monitor (all by default). The value will always be resolved first unless it is prefixed by + in which case it is treated as numeric only. Values that do not resolve but appear to be numeric are used as numeric 🧚
• -P, --processes — Only show processes. Normally iotop shows processes and all threads 🧵
• --no-processes — Show processes and all threads 🫶
• -a, --accumulated — Show accumulated I/O instead of bandwidth. In this mode, iotop shows the amount of I/O processes have done since the process or iotop started. Note that this option and --accum-bw are exclusive and they will turn each other off 🔥
• --no-accumulated — Show bandwidth (useful when changing config file with --write) 💾
• -A, --accum-bw — Show accumulated I/O as bandwidth for the whole sampling period. In this mode, iotop shows the amount of I/O per second for the whole period since the process or iotop started. Note that this option and --accumulated are exclusive and they will turn each other off ⚡
• --no-accum-bw — Show bandwidth (useful when changing config file with --write) 💾
• -k, --kilobytes — Use kilobytes instead of a human friendly unit. This mode is useful when scripting the batch mode of iotop. Instead of choosing the most appropriate unit iotop will display all sizes in kilobytes 📏
• --no-kilobytes — Use human friendly units 🌸
• -t, --time — Add a timestamp on each line (implies --batch). Each line will be prefixed by the current time 🕰️
• -c, --fullcmdline — Show processes' full file path and parameters 🧾
• --no-fullcmdline — Show processes' names only 🏷️
• -1, --hide-pid — Hide PID/TID column 🙈
• --show-pid — Show PID/TID column 👀
• -2, --hide-prio — Hide PRIO column 🙈
• --show-prio — Show PRIO column 👀
• -3, --hide-user — Hide USER column 🙈
• --show-user — Show USER column 👀
• -4, --hide-read — Hide DISK READ column 🙈
• --show-read — Show DISK READ column 👀
• -5, --hide-write — Hide DISK WRITE column 🙈
• --show-write — Show DISK WRITE column 👀
• -6, --hide-swapin — Hide SWAPIN column 🙈
• --show-swapin — Show SWAPIN column 👀
• -7, --hide-io — Hide IO column 🙈
• --show-io — Show IO column 👀
• -8, --hide-graph — Hide GRAPH column 🙈
• --show-graph — Show GRAPH column 👀
• -9, --hide-command — Hide COMMAND column 🙈
• --show-command — Show COMMAND column 👀
• -g TYPE, --grtype=TYPE — Set GRAPH column data source. Accepted values for TYPE are io, r, w, rw and sw. 📊
• -R, --reverse-graph — Reverse GRAPH direction - show most recent values on the right side 🔄
• --no-reverse-graph — Do not reverse GRAPH direction - show most recent values on the left side 🔁
• -q, --quiet — Suppress headers before each run (implies --batch). This option can be specified up to three times to suppress the output of different header lines:
  • -q column names are only printed on the first iteration,
  • -qq column names are never printed,
  • -qqq the I/O summary is never printed 🤫
• -x, --dead-x — Show exited processes/threads with letter x instead of inverse background 💀
• --no-dead-x — Show exited processes/threads with inverse background 🪦
• -e, --hide-exited — Hide exited processes 🫥
• --show-exited — Show exited processes 👻
• -l, --no-color — Do not colorize values 🚫🌈
• --color — Colorize values. This will override the effect of the environment variable NO_COLOR when explicitly specified on the command line. 🌈
• -T, --hide-time — Do not show time clock in upper right corner ⏳
• --show-time — Show time clock in upper right corner 🕰️
• --si — Use SI units of 1000 when printing values. The default is non-SI 1024 🔢
• --no-si — Use non-SI units of 1024 when printing values 🔢
• --threshold=1..10 — Set the threshold to switch to next unit. The default value is 2 🎚️
• --ascii — Disable using Unicode 🔤
• --unicode — Use Unicode drawing chars 🎨
• -N, --inverse — Use inverse interface (black on white) ⚫⚪
• --filter=REGEX — Filter processes by TID and COMMAND. This will only show processes where TID or COMMAND are matching the REGEX. 🔎
• -W, --write — Merge the preceding options to the current config, save the config and exit. Note that all options after this one will be ignored. 💅

⌨️ KEYBOARD SHORTCUTS 💅✨

bestie, these keys are your little remote control. press them, slay, repeat. 💖

• q, Q — Exit. bye bestie, you ate 👑
• W — Save current settings to configuration file in a place conforming to XDG Base Directory Specification. The respective path is created in case it does not exist. In case of error creating or accessing the config file, the error is silently ignored and the configuration is not saved.
  • $XDG_CONFIG_HOME/iotop/iotoprc — if environment variable XDG_CONFIG_HOME is set.
  • $HOME/.config/iotop/iotoprc — if environment variable XDG_CONFIG_HOME is not set but HOME is set.
  • .config/iotop/iotoprc — if neither XDG_CONFIG_HOME nor HOME are set.
• D — Reset all settings to their default values. factory reset, but make it cute ✨
• <space>, r — Toggle sort order. flip it, reverse it, periodt 💅
• <home> — Scroll to the top of the list. take me to the top, main character energy 👑
• <end> — Scroll to the bottom of the list. and down we go 🦋
• <page-up> — Scroll one screen up. one screen closer to the sky ✨
• <page-down> — Scroll one screen down. one screen deeper into the lore 🌊
• <up> — Scroll one line up. baby steps, bestie 🐾
• <down> — Scroll one line down. we love a gentle scroll 💖
• <right> — Sort by next column. next column, next vibe 🌈
• <left> — Sort by previous column. back it up, rewind 🎀
• <esc> — Cancel ionice or filter selection. In case only the help window is open then close it. escape the situation, we love boundaries 💅
• o, O — Toggle showing only processes with IO activity. only the busy ones, we stan a filter ✨
• p, P — Toggle showing processes/threads. processes or threads, choose your fighter 👑
• a, A — Cycle showing accumulated/accum-bw/current values. the data is data-ing 🔥
• ? — Toggle showing inline help. when in doubt, ask the question mark 🧚
• h, H — Toggle showing window help. help window says hi 👋
• c, C — Toggle showing full command line. show me the whole command, no secrets 💖
• 1, 2, 3, 4, 5, 6, 7, 8, 9 — Toggle showing the column (column number corresponds to the shortcut). one key, one column, so satisfying 🌈
• 0 — Show all columns. all of them, every single one, periodt 💅
• g, G — Cycle GRAPH source (IO=IO, R=DISK READ , W=DISK WRITE, R+W=DISK READ+DISK WRITE, SW=SWAPIN). Using g will cycle forward and G will cycle backward. graph go brrr 📈
• R — Toggle reverse GRAPH direction. reverse card, uno! 🃏
• i, I — IOnice a process/thread (depends on process/thread display mode). be nice, or else 😌
• f, F — Change UID and PID filters. filter by UID and PID, we love a targeted search 🎯
• u, U — Toggle using Unicode/ASCII characters for pseudo graph. unicode or ASCII, both are valid 💖
• l, L — Toggle colorizing values. color makes everything better, no cap 🌈
• n, N — Toggle inverse interface (black on white). inverse interface, black on white, iconic 👑
• x, X — Toggle the display mode of exited processes/threads between letter x and inverse background. exited but still showing up, ghosting fr 💀
• e, E — Toggle the display of exited processes. show the exited ones or hide them, your call 💅
• T — Toggle the display of time clock in upper right corner. clock in the corner, it's giving time management ⏰
• s, S — Toggle freeze of data collection. freeze! stop! hammer time 🧊
• Ctrl-B, b — Toggle SI units. SI units, we love the metric system 💖
• Ctrl-R, t — Cycle unit threshold. threshold cycle, round and round 🔄
• Ctrl-T — Toggle task_delayacct kernel sysctl. kernel sysctl says hello 🐧
• Ctrl-L — Redraw screen. refresh, refresh, refresh ✨
• / — Change search regular expression. While the search regular expression is being edited, there is an indicator next to it that shows if the expression is valid. The search is confirmed by <enter> or cancelled by <esc>. regex girlies rise 💅

List of shortcuts in the editor:

• <esc> — Cancel editing and remove the regular expression filter. escape the regex, we love an exit strategy 🚪
• <enter> — Confirm the current regular expression and exit edit mode. In case the regular expression is empty or invalid it will match everything. enter to confirm, slay ✅
• Alt/Meta-<backspace>, Ctrl-W — Delete one word from cursor to the left. delete that word, left side 🧹
• Alt/Meta-D — Delete one word from cursor to the right. delete that word, right side 🧽
• Alt/Meta-B, Ctrl-<left> — Move the cursor to the beginning of the word on the left. jump to the left word start, iconic 👑
• Alt/Meta-F, Ctrl-<right> — Move the cursor after the end of the word on the right. jump to the right word end, periodt 💅
• Ctrl-A, <home> — Move the cursor to the leftmost position. all the way left, home sweet home 🏠
• Ctrl-E, <end> — Move the cursor after the last character. all the way right, end game 🌈
• Ctrl-B, <left> — Move the cursor to the left. left, left, left 🎀
• Ctrl-F, <right> — Move the cursor to the right. right, right, right 🦋
• Ctrl-H, <backspace> — Delete the character left of cursor. backspace goes brrr 💥
• Ctrl-D, <del> — Delete the character under the cursor. delete under cursor, no hesitation 💅
• Ctrl-K — Delete from the character under the cursor to the end of the line. cut the rest of the line, slay ✂️
• Ctrl-U — Delete everything. nuke it, start fresh 💣
• [anything-else] — Non-printable characters are ignored. Normal characters are inserted before the character under the cursor. UTF-8 sequences are parsed and treated as a single character. Unicode combining characters will be appended to the character under the cursor. the catch-all, and it's lowkey iconic 🌟

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🌍 ENVIRONMENT 🌈

• NO_COLOR — As per the recommendation of https://www.no-color.org/ iotop honors the contents of the environment variable NO_COLOR and when it is set to a non empty string, all color output is suppressed. no color means no color, bestie 💅
• HOME, XDG_CONFIG_HOME — Used to determine the config file path. See the W shortcut for details. config file detective work 🕵️‍♀️
• IOTOP_NO_RENICE — Disable the i shortcut. The user will not be able to change processes' nice values. no nice for you 😤

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👀 SEE ALSO 👀

• ionice(1)
• top(1)
• vmstat(1)
• atop(1)
• htop(1)

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👑 AUTHOR 👑

The original Python iotop implementation was written by Guillaume Chazarain. This rewrite in C was started in 2014 by Vyacheslav Trushkin and reworked to include all missing features from the original Python code and several new ones from 2020 to 2025 by Boian Bonev.

This manual page was started by Paul Wise for the Debian project and is placed in the public domain.

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this page is from January 13, 2025 and it's the IOTOP(8) manual. stay iconic, bestie 💖✨