I was hoping to compare resource utilization and performance between 40 Docker instances each with 20 connections vs. 1 process.
It's not even clear whether or not the author actually hit any external websites: In order to have a quick test , I just build a nginx hello page in my cloud server. Then scale it up to a list of 1000000.
It's just a tutorial about how to use docker and celery to build a distributed system. I will have more test about the performance of multiprocess/threads/concurrencies or some other library that supports these technics. In this case, if you don't know how to or even don't want to build a test web server, some big sites like example.com could be your choice. BUT please be gentle to these public sites.
Thanks for your comment.