How to create a big list of different UUIDs, efficiently?

I want to generate tickets for an event. I need to generate a lot of them and I decided to have the ticket number as UUIDs. The question is how to generate a big list of UUIDs and it to be different.

I know the easy way to just check every new UUID generated in the already existing list, but this is not very performance friendly. :)

I am using NodeJS with UUID v4.

Thank you!