Top, htop, nmon: System monitors in terminal

Those of us who work a lot in the terminal, either on our own computer or with servers, often need to see the performance of the equipment, consumption of
RAM, processes that consume the most, CPU, etc., for this there are several alternatives, several programs that we can use to display this information (and more) in the
terminal.

Top:

To run it in a terminal type the following and press Enter:

top

This is the simplest, it is installed by default in many distros and it shows us a lot of different information. For example, it shows us the number of users
assets, online time, also as we can see it shows us the amount of tasks or processes (Tasks: 154 total), the amount of them that are in
running, sleeping, detained or in zombie mode.

Below we see (in KiB) the amount of RAM being used (and free), just like the SWAP

Finally we have a list of the processes, of each one we can know the PID, user who executes it, amount of memory (real and virtual) that it uses, percent
CPU consumption, execution time and specific command / process.

top

As you can see it is a bit uncomfortable to read this information, however, if you press Z will be able to see the information with colors, which does a little
simpler to read all this data:

top-color

To get out of top just press Q and it will close.

htop:

To run it in a terminal type the following and press Enter:

htop

In several distros it is installed by default, in others (like ArchLinux) not, so if it is not opened with the previous command then they must install it.

If they use Ubuntu, Debian or derivatives it would be:

sudo apt-get install htop

If they use ArchLinux or derivatives it would be:

sudo pacman -S htop

htop

As you can see, this shows us the more ordered information, less stuck, it is easier to read everything. It shows us almost the same as the previous top, no
However, in a better way to read it (even with 'bars' for the consumption of CPU, RAM and SWAP), but !, it offers us other options that you can see below.
These options can be used by pressing the keys F1 ... F2 ... and so on until F10, these allow us
search for specific processes in the list, see them arranged as a tree (processes and threads or associated processes), filter by those with more CPU or RAM
consume, kill processes, etc.

To get out of top just press F10 and it will close.

nmon:

This allows us to further customize the information that it shows us, when we open it it shows us several options, to put it simply, it gives us the
information in a modular way, that is, if we want it to only show us the info related to the CPU, we press a key, if we want it to also show us
In addition, the one related to RAM, we press another key, here is the screenshot of the home screen:

nmon-start

As you can see, if you want to see the information related to the CPU press the key c … The one related to the memory key m ...
with hard drives the d ... the kernel k ... the network n (lowercase), etc.

I leave you the combination of nmon + c + m + k

nmon-options

This should be installed, if you use Ubuntu, Debian or derivatives it would be:

sudo apt-get install nmon

If they use ArchLinux or derivatives it would be:

sudo pacman -S nmon

To get out of top just press Q and it will close.

The end!

Well this has been it. If any of you know any other terminal system monitor, let me know in a comment in real time 🙂

regards


Leave a Comment

Your email address will not be published. Required fields are marked with *

*

*

  1. Responsible for the data: Miguel Ángel Gatón
  2. Purpose of the data: Control SPAM, comment management.
  3. Legitimation: Your consent
  4. Communication of the data: The data will not be communicated to third parties except by legal obligation.
  5. Data storage: Database hosted by Occentus Networks (EU)
  6. Rights: At any time you can limit, recover and delete your information.

  1.   wow said

    long live htop! I would like to emphasize the main difference that affected me the most compared to top: in top the RAM consumption that marks you is the total, while in htop, and thanks to the colors, you clearly differentiate the active RAM from the passive one (green and yellow), being able to clearly see the total consumption on the bar and differentiate the real consumption (which would be the active one) from the temporary memory content (passive)

    1.    wow said

      mmm I had to change the useragent to get me a manjaro ... is there a way not to overwrite the entire useragent? That is, when I override it, I have to take care of updating my version of Firefox (for example) since some pages for compatibility look at the version you use through the useragent, and when overwriting the default I have to edit it by hand each time . What I'm asking is if there is any way to "append" a word to the default useragent, or even just change one of the fields

  2.   Gonzalo said

    I did not know nmon, good data 😀

  3.   RAW-Basic said

    Sandy .. .. 'copypasteaste' in the nmon .. ..we shouldn't install htop again .. ..but effectively nmon .. 😉

  4.   cronos said

    There is an error in the nmon installation code (which by the way I did not know) Thanks for the info.

    1.    KZKG ^ Gaara said

      Thanks for noticing, on Twitter they told me anyway hahaha. I fixed it.

  5.   manolox said

    Top is also interactive.
    For example, pressing "m" orders the processes by consumption of ram memory (by default it comes in order of CPU). Pressing again returns to the CPU order.
    Pressing «k» (for kill) asks us for a PID to enter and kill the process
    Pressing «u» (for user) asks us for a user and will make a filter with the one we enter.
    Pressing "h" helps. You have a lot of options.

    Then as a recommendation for a system monitor in the terminal it would be glances.
    It is more or less a mix of the top + free + ifconfig and other commands. In other words, it lists the active processes, plus the information of the network interfaces, plus the activity of the disks / partitions, plus some data from sensors. Is very complete. It is not interactive, but it is "configurable on the fly".

    1.    KZKG ^ Gaara said

      Thanks for improving this thread 😀

    2.    eliotime3000 said

      Excellent. I'll take a look at the top man.

  6.   poor taku said

    Every day I like the console more and its programs seem to me the pinnacle of programming, tomorrow I'll take a walk around nmon!

  7.   rv said

    Excellent info, thank you!