External MongoDB Use

[Geraldo155]

Hello everyone,
I hope this message finds you well.
I’m a Computer Science student at the Federal University of Campina Grande (Brazil) and part of a research team at the Distributed Systems Laboratory (LSD) working on FinOps initiatives. We’ve been facing some memory consumption issues in the MongoDB StatefulSet and are currently exploring ways to optimize its usage. I noticed that OptScale supports external deployments for some modules, including the MongoDB service.
These external deployments would allow me to use the --inMemorySize attribute when installing the database, which doesn’t seem possible in the current deployment.
I found the argument --wiredTigerCacheSizeGB in the current Helm template with the value set to 1 GiB, but it doesn’t appear to be working.
Another way that might help is with the autoscaling of the MongoDB application, since MongoDB offers a native way to handle multiple replicas.
Has anyone tried this approach? Did it work as expected?