Jitsi Load

I was curious about the way Jitsi works. Say I have three simultaneous rooms having 50 members each and other situation where there is only one room having 150 people. Clearly in the second case there should be more load on the Jitsi server as each client has to communicate with 149 other.
Are both situation different or are they similar ?

Load estimation is always a tricky subject.

Jitsi Meet relies a lot on the bandwidth, not the server cpu/ram, because it doesn’t mix the content. So yes, 150 people in a single room and if all of them are with cameras on, this will put a lot of load on the clients machines. I never seen in real life Jitsi rooms with so many participants, and for example at meet.jit.si there is a configured limit of 75.

If you need more people in the call, maybe you are looking for a solution with streaming, not a webconference one. With Jitsi you can stream to an RTMP server (YouTube or your own) and have all the active speakers in the real call and all the other attendees watching the stream.

Regarding the traffic and bandwidth load - there will be no significant difference.