High CPU on app deploy w/high number of active users?

We’re hosting an app on on Modulus.io with approx 11k concurrent sessions. When we deploy or restart our app, we see that the CPUs gets pinned at 100% for about 5 minutes. We can only speculate that this is because Meteor is reestablishing subscriptions/websocket connection with all the clients. During this time, no data loads in the app and it is unusable.

Has anyone experienced issues with high CPU on Meteor app bootup?


how many sessions per core?

Those 11k sessions are spread out over 30 Modulus servos, so avg ~360/servo. Is that what you mean?

Not sure modules deploy their containers. Ideally it should need to something like rolling deployment with some time in between deployments. I they don’t do it, try Galaxy.

After talking with some other folks, this is apparently a common issue with large Meteor apps. Meteor Galaxy works around it with rolling deploys, so the startup load is distributed over time.

This is not a good sign but maybe this is something that hosting providers can support for meteor apps.

I’m mostly interested in the cost at scale I believe this is going to be the biggest long term issue with meteor apps that scale. I wonder if you can share your server sizes.

Is it’s the mid size one than $28.80 * 30 or $288 for 10 which is on their site so your looking at $864 per month.
I wonder what happens on long term growth.

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We’re at 30 servos at 1GB a piece. We have an enterprise deal so we’re paying about half that.

Can you add your thoughts and feedback here Meteor cost at scale will this become a major issue?