iotop

Tools for monitoring disk I/O usage

Supplementary instructions

iotop command is a top tool used to monitor disk I/O usage. iotop has a UI similar to top, including PID, user, I/O, process and other related information. Most of the IO statistics tools under Linux, such as iostat and nmon, can only count the reading and writing of the per device. If you want to know how each process uses IO, it will be troublesome. You can use the iotop command to check it easily.

iotop is written in Python language and requires Python2.5 (and above) and Linux kernel2.6.20 (and above). iotop provides source code and rpm packages, which can be downloaded from its official homepage.

Install

Ubuntu

apt-get install iotop

CentOS

yum install iotop

Compile and install

wget http://guichaz.free.fr/iotop/files/iotop-0.4.4.tar.gz
tar zxf iotop-0.4.4.tar.gz
python setup.py build
python setup.py install

grammar

iotop (option)

Options

-o: Only show processes with io operations
-b: Batch display, no interaction, mainly used for recording to files.
-n NUM: Display NUM times, mainly used in non-interactive mode.
-d SEC: Display every SEC seconds.
-p PID: monitored process pid.
-u USER: Monitored process user.

Commonly used shortcut keys for iotop:

1. Left and right arrows: Change the sorting method. The default is to sort by IO.
2. r: Change the sort order.
3. o: Only processes with IO output are displayed.
4. p: Switch the display mode of process/thread.
5. a: Displays the cumulative usage.
6. q: Exit.

Example

You can see the effect by executing iotop directly:

Total DISK read: 0.00 B/s | Total DISK write: 0.00 B/s
   TID PRIO USER DISK READ DISK WRITE SWAPIN IO> command
     1 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % init [3]
     2 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kthreadd]
     3 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [migration/0]
     4 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [ksoftirqd/0]
     5 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [watchdog/0]
     6 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [migration/1]
     7 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [ksoftirqd/1]
     8 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [watchdog/1]
     9 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [events/0]
    10 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [events/1]
    11 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [khhelper]
2572 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [bluetooth]