in Mariadb - Can you cache the indexes and data for Aria Storage engine tables?
As for now
We plan to also add CACHE INDEX for Aria tables if there is a need for this.

And as you can see that it is written in https://mariadb.com/kb/en/cache-index/ so that it would be more like the MyISAM, but as development and theory grows in time, we will see and wait, what they actually want to do qand implement.