RealmConfiguration constructor with compactOnLaunch

[Oshuremy]

Hi,

I never paid too much attention to RealmConfiguration creation in my app but today I want to had compactOnLaunch with callback. And I discover that this callback is called everytime getInstance is used. But if I let one Realm instance without close, the next time I will make getInstance the callback of compactOnLaunch isn't call.

Generally it's better to have 1 realm instance for all and close when the app is close OR 1 realm instance each time we want to read/write on realm and close it immediatly ?
(For me the second is better but in that case compactOnLaunch is called everytime.)

Can you help me understand this better.
Thank you