Thursday, July 17, 2014

Introducing vtop — A Terminal Activity Monitor in Node.js

Command-line tools like “top” make it difficult to see CPU usage across multi-process applications (like Apache and Chrome), spikes over time, and memory usage.
That’s why we created vtop.
Vtop is a free and open source activity monitor for the command line. It’s written in node.js and can be easily extended. Why not check out the source code?

How to install

If you haven’t already got Node.js, then download that first, then run:
sudo npm install -g vtop


This is pretty simple too.

Keyboard shortcuts

  • Press ‘u’ to update to the latest version of vtop.
  • Arrow up or k to move up the process list.
  • Arrow down or j to move down.
  • g to go to the top of the process list.
  • G to move to the end of the list.
  • dd to kill all the processes in that group


How does it work?

It uses Unicode braille characters to draw CPU and Memory charts, helping you visualise spikes. We also group processes with the same name together.

I think the CPU % is coming out wrong.

We calculate the CPU percentage as a total of your overall system power. 100% is all cores and HyperThreads maxed out. This is different to how Apple Activity monitor works.

Can I change the color scheme?

Sure, just do:
vtop --theme wizard
This loads the theme file in themes/ with the same name. Make your own and send me a Pull Request
You could add this to your aliases if you’d like to use it always.
alias vtop="vtop --theme brew"

What about measuring server req/s, log entries, etc etc?

Yeah that’s on the list. Feel free to send a pull request though. Check out the sensors/ folder.

What license is this under?

MIT – do what you like with it.

I have another problem that’s not answered here

Please open a ticket and we’ll take a look for you.

Interested in working at Parallax?

We have a front-end developer position open at the moment