Optimization guru - jabber question?

Question

JavaScript

Question to the server optimization/loading circle:

There are two options.

The first option, internal mail is built on the basis of a simple chat made on ajax
The second option, internal mail is made on the basis of jabber, and the site is also issued using ajax

When working with jabber, a free server will be used (temporarily)
User activity at the moment is 100 -200 people online, we count on a higher audience

Question:

Dear GURU, what will load our server more? Jabber, which we will later transfer to our server? Or our self-written script.

Pros of the first option:
Already done and everything works

Pros of the second option:
Work with funds from external clients
Numerous statuses ala “they write to you”
And of course, all the other joys of jabber

Answer 1

XMPP servers tend to be pretty fast with a lot of users online. But there it is still necessary to solve the problem with storing history and searching for it. I can’t say how convenient it is to shift this functionality completely to the server.
When I did such functionality, I decided not to bother, and store the history in the site database. The client clings to XMPP through JS (Strophe). The history is saved by Ajax. It’s crooked, but I didn’t come up with anything more beautiful quickly.

Answer 2

ejabberd2 is as fast as diarrhea.
If the gabber functionality covers your tasks, then this option will be faster.