I am trying to mimic the simulation in this post (https://flowingdata.com/2015/12/15/a-day-in-the-life-of-americans/). I've got something to work for about 100 node, but when I increase the number of nodes to ~1000 it get very very slow and jaggy. I could not figure out how it was possible in the post to simulate 1000 particle collisions so smoothly.

I should mention I am using d3 v4 while the post is using d3 v3. The force API in d3 have changed

any help is much appreciated