EmptyCrate Software. Travel. Stuff.

By default, all views and stored routines in MySQL run with the privileges of the definer, not the invoker. This is equivalent to the setuid bit in Unix.

In the case where you need to provide execute permissions to stored routines (via EXECUTE) to a read-only user, it is possible to inadvertantly give your read-only user the ability to modify data. If the user has access to a stored routine that modifies data, then the user will be able to modify data.

If you have dozens or hundreds of threads doing work they are probably producing some sort of output. I'm not referring to logger output, but to permanent storage, perhaps in a database. If you cannot store the data as quickly as you produce it, you will eventually run into problems. If you are just barely able to keep up with data storage then your scalability will be limited.