Super slow config load time (huge config)

[GibMeMyPacket]

Hello,
I have been recently working on something and have been trying to know the limitations.

I tried to load a huge config with 20 inbounds and 100K users per inbound, It already took 1 hour and still counting!

Imagine a VPN/Proxy business that a user should have access to all the servers (like all the existing VPN providers), 100K ain't much.

What do you do? do you add users via api calls upon each xray restart? is that faster?
I have tested to add those users via xray api calls but that wasn't fast too, not sure if i can do it multi-threaded (goroutines).

Process Hacker's performance monitor:

The machine has Intel Core i7-8th generation with 32 GB RAM (way faster than most proxy servers)

Any advice on how to make it?