The Sundarban
Published Apr 11, 2026, 4:00 PM EDT
Afam’s expertise in tech publishing dates back to 2018, when he worked for Make Tech Easier. Over the years, he has constructed a reputation for publishing excessive-quality guides, opinions, guidelines, and explainer articles, covering Windows, Linux, and start supply instruments. His work has been featured on prime web sites, including Technical Ustad, Windows Document, Guiding Tech, Alphr, and Next of Windows.
He holds a first stage in Laptop Science and is a strong advocate for data privacy and safety, with several guidelines, movies, and tutorials on the subject published on the Fuzo Tech YouTube channel.
When he is no longer working, he likes to utilize time with his family, cycling, or tending to his garden.
Regardless of my Linux distribution or setup, there comes a point when I start experiencing some slowdown or lag in daily activities. Sometimes, it will get tricky because when I employ prime, CPU and reminiscence usage peep normal.
I lately tried iotop, and in real time, it revealed apps that have been reading or writing to my disk, an aspect I typically fail to spot when faced with performance issues. iotop is now one among my accelerate-to commands for troubleshooting Linux.
Install iotop in seconds
Uncomplicated to status up, but there’s one detail most guides miss
To install iotop on Debian-based distributions such as Ubuntu or Mint, bustle:
sudo apt install iotop
On Fedora bustle sudo dnf install iotop; on Arch bustle sudo pacman -S iotop .
There are two variants of this software: the regular iotop (Python-based) and iotop-c (written in C). iotop-c is a more moderen model and becomes the automatic default whilst you install iotop on some fashionable Ubuntu and Debian systems. Even though it is almost unimaginable to repeat them apart from the interface, iotop-c is smoother in daily employ. On distros that supply iotop-c, it is usually the higher preference.
The #1 start supply operating gadget powering hundreds of thousands of PCs and laptops around the sector.
Understand what iotop is really telling you
The few numbers that actually reveal disk stress
The total iotop interface is overwhelming, but whilst you acknowledge that mighty of it may be irrelevant, it becomes easier to interpret. I typically search the advice of four columns for diagnosis:
DISK READ: Shows bytes read per 2nd
DISK WRITE: Reveals bytes written per 2nd
IO%: % of time the job/thread spent doing I/O (waits + swapin)
COMMAND: Shows the job name
I repeatedly skip the stay portion because viewing the total disk activity isn’t very beneficial whilst you want to track down the cause. I recuperate insights looking thru the list below, and the most consequential flags are -o and -a. With -o, I obtain a extra streamlined list including only processes at expose executing I/O. -a takes me to the accumulated mode the place I search totals of bytes read or written since iotop started.
Most of my diagnoses happen with the -o flag. -a is a last resort if I really feel there is an intermittent prevalence of a issue, occasional stuttering, temporary lag while opening files, or when I enact no longer find anything on iotop’s reside peek.
arch
How I employ iotop to catch the exact job
A real workflow that turns disk activity into a clear answer
I realized I wanted iotop when my gadget became sluggish, and the regular gadget displays that I employ wouldn’t catch the culprit. After installing it, I ran the command: sudo iotop -o -d 2Within a few seconds one job settled at the stay. I advise slowing the refresh rate so that it is easier to catch patterns (that’s what -d 2 in the command does). When I seen this job, I saw the continuous disk writes that happened thru refresh cycles. It was the duration that stood out because rapidly spikes are normal.
My browser had a job constantly writing megabytes to my disk, and with this observation, I may rule out other that you can imagine culprits. On other occasions, I have been able to catch utterly different processes causing lengthy spikes:
A backup job (rsync) writing steadily
A package manager pulling updates
A logging carrier writing extra than anticipated
The rule of thumb of thumb is to investigate if you peep a job remains at the stay, generating I/O for extra than one refresh cycles. iotop will get rid of any guesswork because it shows you both activity and an exact name.
Related
I switched to Hyprland and now I obtain why Linux users are smitten by it
Whereas I am going to sustain it on my Waylands, I am going to refrain on my Minty daily driver. For now.
What to enact if you find the culprit
Turn visibility into action with out breaking anything
I develop no longer immediately assassinate a job that is writing large amounts to disk. In fact, the exact step I take is dependent upon what the job is. Adjusting an application’s settings or closing it entirely is reasonable when the culprit is a user application. You can also investigate what’s triggering that action. In the case of a browser, there may be an extension causing the spikes or aggressive caching.
Nonetheless, when it is a job I am no longer familiar with, I develop no longer assassinate it straightaway. I desire to enact a Google search to learn extra about it and determine if it is safe to assassinate.
Also, no longer all processes you search at the stay are a signal of unpredictable behavior. Kernel threads appreciate kworker and jbd2 can be normal—jbd2 is tied to ext4 journaling and may be excessive during heavy writes; kworker is a general kernel thread that can appear for many reasons. To inspect a job, bustle lsof -p to search for the files it accesses.
