How frequently does the bug occur?

Sometimes

Description

Hi Realm team,

I am filing this ticket as requested by @ianpward over email. This is an inquiry about realm performance around Mongo queries, and is a reference for your investigation. I do not believe this issue is specific to realm-js.

App Services https://realm.mongodb.com/groups/632e05374a332334728f1257/apps/638f4bbacfca527011d14f65/dashboard

App ID: stashpad-bbbqw

Our Atlas cluster frequently scales up and down due to high CPU usage. There appears to be a high number of disk scans as a part of realm syncing between devices and the app services data.

In general, the scaling happens more frequently than we'd expect for having only a couple of hundred concurrent users at the most.

As a specific example, here is a spike that caused us to scale from M20 -> M30.

Though there was a relatively small amount of data transferred according to the app services app.

We were not initially concerned by the amount of scaling but were contacted by a MongoDB customer success rep who suggested that scaling this frequently is bad, and that our cluster was having a high number of disk scans and in memory sorts.

Please let me know if I can provide any more information to help further this investigation.

Stacktrace & log output

No response

Can you reproduce the bug?

Sometimes

Reproduction Steps

Normal use of the Realm JS SDK in both a react native app, and an electron app.

Version

11.10.1

What services are you using?

Atlas Device Sync

Are you using encryption?

No

Platform OS and version(s)

N/A

Build environment

No response

Cocoapods version

No response