Disabling sync on a specific collection

I have several Realm instances running on the same cluster, each tied to a different client-app (Kotlin, Swift). I’ve noticed that one client in particular has far more writes to a specific collection (“History”) than expected.
I know about pausing sync for the entire Realm, but is there an easy way to pause/disable syncing of just the History collection without impacting syncing of other collections, and without affecting the local creation of History entries for end-users? Thanks!

Hi Johannes,

Thanks for posting and welcome to the community.

Are you referring to the History collection of the __realm_sync database or is this a collection in a database you created?

Please know that __realm_sync.history is used to store metadata about Sync operations which is crucial to how Sync works. This db is hidden in Atlas data explorer so you will need to use Compass or MongoShell to read it.


Hi Mansoon, thanks for you reply. This is a collection that I created, not the internal one.
My main concern here is performance - I’d like to know if there’s a good way I can pause syncing on less-important collections at times of high load.

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@Johannes_Deva-Koch did you manage to find a solution ?


Since the term “collection” doesn’t exist on the client side I’m not sure I understand the use case. Could you please describe in more detail the reasons of this request and the nature of the performance issues you are trying to solve?


Hi guys, thanks for getting back. I’ve been in touch with some of your colleagues in support, and we’ve figured out the performance problems (mostly too many writes from our apps). Thanks anyway!