Node red web page not loading or slow loading

That is interesting and slightly worrying.

Some questions:

  • What version of Node-RED and Node.JS are you using?
  • Is this on a Pi? If so, what version of the hardware?
  • Can you check your swap? Is the Pi paging a lot of data in and out of swap? That will absolutely kill the performance of a Pi since it has to use the very slow SD-card.