MongoDB Realm vs. Stitch login times - why is Realm so slow?

Question

I've built a web tool using MongoDB databases hosted on Atlas, connected via Stitch. From what I understand, Stitch is now depreciated and has been turned into MongoDB Realm. So I tried to update my site, using the new Realm App instead of Stitch. While it does work, anonymous log-ins are now much slower for some reason. I did some quick testing, using the code suggested in the MongoDB documentation:

let t0 = performance.now()
app.logIn(Realm.Credentials.anonymous()).then(() => {
         let t1 = performance.now()
         db.collection('test').find({
                category: "test"
            }, {limit: 10})
        console.log("Login took " + (t1 - t0) + " milliseconds.")
    })

It takes me an incredible 1200 ms to log in.

let t0 = performance.now()
app.auth.loginWithCredential(new stitch.AnonymousCredential()).then(() => {
            let t1 = performance.now()
            db.collection('test').find({
                category: 'test'
            }, {limit: 10}).asArray()
            console.log("Login took " + (t1 - t0) + " milliseconds.")
        })

With the old Stitch App, it usually takes under 20 ms to log in.

Any ideas what's going on here or how to solve this? I do know that there is the possibility to first authenticate a user as described in their documentation, however I tried that and it's just as slow.

Is there actually a need to update to the new Realm App, e.g. will the old Stitch implementation stop working in the not too distant future? Any info on that would be appreciated ;)

Update: I did a bit more investigating, and it seems the reason why Realm is slower comes from the fact that logging in using logIn(Realm.Credentials.anonymous()).then(() => ... results in two Post requests, but using auth.loginWithCredential(new stitch.AnonymousCredential()).then(() => ... does the authentication and content download all in one request. With Realm I twice get a 500-700 ms TTFB waiting time, with Stitch that happens just once.

Answer 1

I'm creating an application's backend from scratch with MongoDB Realm currently. I am using their Web SDK to authenticate using email-password credentials. My round-trip performance averages around 600-800 ms.

For my application (using a Vue frontend), this is acceptable to me. I don't know what your requirements are, but you may want to try using the new SDK. Unfortunately, I'm encountering poor query performance with the GraphQL endpoint service Realm provides. According to a thread I started on their forum, their engineers are looking into it.