Database Sizes:

Friendica (MariaDB): 31 GB for 700 users
Mastodon (PostgreSQL): 15 GB for 1000 users
Matrix-Synapse (PostgreSQL): 5 GB for 1 user
XMPP (PostgreSQL): 0.4 GB for 200 users

CPU times according to xentop:

Webserver VM (Matrix, Friendica & Mastodon): 13410130 s / 130%
XMPP VM: 944275 s / 5.4%