Linux I/O Performance measurements with iotop

The Linux monitoring-tool iotop shows the current I/O transfer rates for the ongoing processes/threads. It uses the I/O usage information of the Linux kernel (requires Linux kernel version 2.6.20 or newer).

The following example shows the output of iotop on a laptop with Ubuntu 10.04:

admin@admin-t410-ubuntu:~$ cat /proc/version
Linux version 2.6.32-22-generic-pae (buildd@palmer) (gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5) ) #36-Ubuntu SMP Thu Jun 3 23:14:23 UTC 2010
admin@admin-t410-ubuntu:~$ sudo iotop -b -n 1
Total DISK READ: 49.06 M/s | Total DISK WRITE: 0.00 B/s
  TID  PRIO  USER     DISK READ  DISK WRITE  SWAPIN      IO    COMMAND
 3347 be/4   admin    49.06 M/s   49.06 M/s  ?unavailable?  cp CentOS-5.4-x86_64-bin-DVD.iso CentOS-5.4-x86_64-bin-DVD-kopie.iso
 2560 be/4   admin     0.00 B/s    0.00 B/s  ?unavailable?  twinkle
[...]

More information

• iotop Webseite
• From the everyday life of a sysadmin: LUG Camp and Iotop (Linux magazine)
• Linux per-process I/O performance: measuring the wrong thing (taint.org: Justin Mason's Weblog)

Author: Werner Fischer Werner Fischer, working in the Knowledge Transfer team at Thomas-Krenn, completed his studies of Computer and Media Security at FH Hagenberg in Austria. He is a regular speaker at many conferences like LinuxTag, OSMC, OSDC, LinuxCon, and author for various IT magazines. In his spare time he enjoys playing the piano and training for a good result at the annual Linz marathon relay.

Translator: Alina Ranzinger Alina has been working at Thomas-Krenn.AG since 2024. After her training as multilingual business assistant, she got her job as assistant of the Product Management and is responsible for the translation of texts and for the organisation of the department.