Make mariadb default for hass.io

I think it makes sense to use mariadb by default instead of sqlite for hassio installation images. I’ve used a plugin to enable mariadb after I ran into serious performance problems on a rpi 3b+ and it made everything much more responsive. Is there a reason for using sqlite over a preconfigured mariadb instance?

Because mariaDB uses way more resources than SQLite – it might have worked for you on a 3B+, but might not work for everyone, especially on lesser hardware.

You can override the default SQLite with the Recorder component if you want to switch to a “real” db.

For other devices that might indeed be problematic, however on the pi 3b+ sqlite uses a lot more CPU resources than mariaDB. Obtaining records for history graphs would slow down the pi and take way too long when using sqlite, which in my opinion really hurts user experience.

I do get that device specific optimisations could cause a mess, so maybe adding a warning in the getting started guide or on the history graph page would be a better option? As I suspect that this poor performance will occur for everyone who tries to use a history graph on a raspberry pi like device. I had to find out that sqlite was the cause of this issue by browsing through a lot of forum topics, which is not something every new user is likely to do.

I vote changing the numbers of days to keep data. The default I think is 10. I would make it 2 by default.