How do I build my application with high throughput in mind? (Need guidance)

I am building a Spring boot REST API app that is part of a microservice architecture project. What I am planning: My app listens for events from two other services and after some business logic, logging, calculating, and persistence I have to publish my results to another rabbit MQ exchange. The first two services listen to pings every 10 seconds from 15,000 devices each and publish their data to queues that I listen to. My current plan: I need some sort of cache to keep track of events sent from both services because I need data from both at a time interval to do my logic. I am using an in-memory hashtable and I am sorting the values in this hashtable everytime I update it. My hashmap is a Map where the first key is a regionID and the second map is keyed based on deviceID. This sorting is done on the internal map and I suspect might become the bottleneck. Is a single shared key value datastructure storage a good way to go with this or is there something else I should try?

May 3, 2025 - 16:39

I am building a Spring boot REST API app that is part of a microservice architecture project. What I am planning:

My app listens for events from two other services and after some business logic, logging, calculating, and persistence I have to publish my results to another rabbit MQ exchange.
The first two services listen to pings every 10 seconds from 15,000 devices each and publish their data to queues that I listen to.

My current plan:

I need some sort of cache to keep track of events sent from both services because I need data from both at a time interval to do my logic. I am using an in-memory hashtable and I am sorting the values in this hashtable everytime I update it.
My hashmap is a Map> where the first key is a regionID and the second map is keyed based on deviceID. This sorting is done on the internal map and I suspect might become the bottleneck.

Is a single shared key value datastructure storage a good way to go with this or is there something else I should try?