How to find the Degree of Browser Parallelism (DoBP) for a page?

Analysis
1

Browsers open multiple connections (limits apply for each domain used by the page) to use idle time. I am exploring whether the concept used by me in industry to determine batch concurrency (batches are scheduled across 24 hours and we need to find the average batch concurrency). Have given a manual example for a web site (with one domain).

https://www.webpagetest.org/customWaterfall.php?test=170903_JD_da7742126d58b23a65c5eb59104c7741&run=3&width=930

Dataimage
Is it possible to calculate the degree of parallelism for a page using a Big Data Query on the requests table (applying the above concept)?

Then want to check if DoBP correlated with time metrics like onload or onrender.

2

Yes, it should be possible. We use WPT under the hood, and our traces have socket IDs associated with each request… You’ll have to do some aggregation to detect “active” time for each socket, and that should then give you what you’re after.