RBAC performance - PHP vs DB

I am wondering about RBAC performance - PHP vs. DB.
Storing into PHP files requires less setup & is directly opcached as PHP file.
That’s why I use it by default.
However I am wondering what would be “reasonable” limit for switching to DB storage?
For example if PHP files (assignments) contain 100k items having filesize e.g. 100 kB would that justify DB-storage instead of files?
Has anyone experience or did some benchmarks ?
Thank you.


I also want to see the benchmarks if it exists.

I’ve been using DbManager with cache enabled.

i personally preferred to store in DB as it is easier to manage the permission and assignments, especially if there are lots of permissions.