How to get metrics of javascript/dom loading and processing time
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We found ourselves working in a webpage that manages to work with >20k users in real time.

We worked so hard to optimize the back-end system but we now need to make optimizations in the front end.

The first thing I came up with was use some tool of monitoring the load time of the JS files.

But we don't really need to get the times of loading javascript, what we really need is know what parts of our javascript code are taking more time to finish.


Now we are using new relic to track our site, and know what server-side scripts need to be optimized.

But I can't see any metrics about front-end codes or witch files need to be optimized.

There's any tool out there that may help us with this?


