Slow connection on jitsi network and limit?

Hi All, first of all Jitsi rocks!!

we integrated Jitsi in Klassroom pointing to “meet.jit.si” while we are developing our own server. What are the limits of your servers? Actually we have 750,000 users and they are all complaining of the reliability of the network and can’t manage to use it very well. Most of our users are in France.

Any advice? If we build our servers, how many calls can a single server handle?

Thank you for your help.