iotop

What iotop is

iotop is a free Linux program that identifies processes making heavy use of input/output requests and lists them by I/O usage. It can show accumulated I/O or bandwidth, with controls for displaying or hiding read, write, swap-in, and I/O percentage columns. Monitoring can focus on selected process IDs or users, or cover processes and threads across the machine. It supports interactive and batch modes, iteration counts, configurable delays, and timestamps in batch output. Command-line filters can narrow the display by TID and by command using a regular expression. The project lists packages or installation instructions for Debian-derived distributions, Fedora, CentOS/RHEL, Void, Arch, and Alpine Linux, and documents building from source with make after development dependencies are installed. iotop is licensed under GPL-2.0+, but installing and using it requires root access. The releases page lists version 1.31 as the latest release; its tag has a verified committer signature, though the signing key has expired.

Who it suits

It suits Linux users who need to inspect process-level I/O activity interactively or in batch output. Root access is required to install and use it.

Limits

The free GPL-2.0+ program requires root access. It supports Linux; remote monitoring, service monitoring, and process alerting are unavailable.

Getting started

1. Open the iotop project website on GitHub.
2. Install using the package or instructions for your Linux distribution.
3. Alternatively, install the development dependencies and build from source with make.
4. Run iotop with root access.

Verdict

iotop offers configurable process-level I/O monitoring for Linux, including batch output and filters. Its root requirement and lack of remote monitoring or process alerting may matter for some users.