SQLite works well with 2k DAUs on a single node, even with Django's not particularly efficient ORM. You just have to be careful about what you really need to write to DB and what's okay to either not save at all, or just throw into a log file for later offline analysis.
I don't see how these guys can think about MAU/DAU to assess DB load and sizing without talking about the rest of the app/arch details. Wouldn't ops/time be more agnostic?
Agreed, number of active users cannot make sense as a generic unit across systems...
I have 2 systems where in the first (route optimization platform), 1 user would, as part of just a normal 10 minute session:
- read ~100MB from the database
- utilize 100% of 32-core machine CPU (and 64GB of RAM)
- resulting in thousands of writes to the database
- and side-effect processing (analytics, webhooks etc)
Over a course of a day, it would likely be ~10x for that single user.
In the other system - appointment scheduling - 1 user would, in 1 day, read ~1MB of data from the database, and make 2-3 writes from a single action, with maybe 1 email triggered.
Can make sense if it's about loading and showing not-too-complicated data, but no intensive computations. Then you can compare roughly similar applications
