[ara4n]

rpdillon is totally right - the term is overloaded. We're using "realtime" exclusively here to mean synchronous human communication - like the RT in WebRTC. In other words, IM or VoIP - anything where you expect to get a response from the other user inmediately rather than waiting asynchronously.

This of course clashes with the RTOS style use of the word, and we aren't claiming that Matrix has any hard realtime timing guarantees at all, other than the soft realtime behaviour media stacks like WebRTC give you by means of high priority threads.

In retrospect it's a confusing term; we should probably avoid using it :)

disclaimer: use of the word realtime in the Matrix.org blurb is all my fault...