Quanta new frontend probes


You may have noticed a new entry in your changelog or a comment on your Web scenarios' charts stating that we deployed an update of our frontend monitoring probes. We're going to give you some additional information and answers to your questions in this article.

If you still have some questions or comments after reading it, feel free to contact us ! We're always happy to share with you. 

First of all, what's that frontend thing again ?

QUANTA measures your web scenarios in 2 different ways :
  • Backend time, which represents the time spent generating the HTML page only (that's the part where your application builds the page).

  • Frontend time, which accounts for the backend time and the time spent by the browser to load the associated elements like Javascripts, CSS, images... This one is the most representative of what a user experiences when he visit your website. 

What's the purpose of this new probe?

We decided to rebuild our frontend probe from scratch in order to improve it's performance and stability. The advantage of this refactoring is that it allows us to build new features and grants better precision in the data we show you.
On the long run, we want to merge the backend and frontend probes to ease reading and improve metrics correlation, thus improving QUANTA usability overall.

What's different with this new probe?

About response time measurements

There are some case in which you'll observe a slight improvements of response times on your frontend scenarios. This difference is due mostly to 2 factors:

  • Better server hardware
  • Faster network connectivity

We see you coming ! That doesn't mean older measures were wrong. We just improved the metrics precision a bit.

About PageSpeed scores

We updated the PageSpeed scoring algorithm to provide you with better recommandations on what really matters. It'll be easier for you and your team to find the optimizations with the higher impact.

For mobile-simulated scenarios, we now use a different recommandation strategy designed for mobile devices. That's why you can observe different scores between your mobile and desktop scenarios.

I heard the new probe captures videos, is that true?

Yep! :)

Please note this video capture system is experimental and we're still working on it. Here is some bugs you can experience from time to time:

  • Video duration different than the reality
  • Poor image quality
  • "Shrinked" images

We still chose to enable this feature despite these little imperfections and we'll fix that in the future.

How do I get the new probe? How can I tell which probe version I'm using?

We'll start to migrate customers starting from the 21st of March 2018 and this rollout will take a few weeks to be completed. There's nothing to do on your side, we're taking care of everything!
When we update a scenario, we insert an event on top of your charts in QUANTA to tell you about the probe switch.
You can also check if a scenario is using the new probe in the Web Scenarios tab of your QUANTA settings.

I'm a bit afraid about this change...

Don't panic! We tested the new probe with intensive workflows before pushing this change to production. Our team will drive the progressive rollout and will make sure everything is operating fine.

Finally, if you have any question if you notice something weird, our support team will be there to help you, feel free to drop us a quick message.

Looks awesome! Is there bad news too?

Well, this is quite a huge change and we had to do some compromises on some features not wildly used.

The following features are not yet compatible with the new probe:

  • It's not possible to chose a different polling region, our new probe is ran from our datacenter in Paris.
  • It's not possible to use a different browser than Google Chrome 64.


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