Force-directed graph drawing Runtime Complexity
According to [1] runtime is 'considered' to be O(n^3) and can be done with clever stuff in O(n^2*log(n)).
For javascript I estimate (based on [2]):
(250000^3) * ms = 495136.948 years
((250000^2) * log(250000)) * ms = 10.6908782 years
A bit too long for your average webuser.
An estimate for an offline precalulation with some programming language closer to hardware (based on my memory about mircobenchmarking in c++17):
((250000^2) * log(250000)) * 10 ns = 56.2285418 min
Seems more reasonably. Unfortunately Graphvis was unable to handle this much data despite being allegedly "capable of handling very large graphs" [3]