Load balancing at a connection level

I have an application with two pods and some client from inside the same cluster connecting to them by a service, as far as I know this will do a connection level multiplexing.

There is no reason for the workload to be consistently higher at one pod than another, yet I can see one of the pods receiving nearly 3 times more load than the other over a period of 3 hours.

The pod with more load was already running when the other pod started.

My first hypothesis was session stickiness, but a quick test shows that the connections are balanced

for _ in `seq 300` ; 
do
   curl -b cookies.txt -c cookies.txt -s riva-api.riva:8002/metrics | grep '^nv_gpu_utilization'; 
   sleep 0.1; 
done | awk '{print $1}' | sort | uniq -c

My new hypothesis is that python riva client is reusing the connections. Does that make sense or we are guaranteed to start a new connection when calling riva.client.ASRService(auth)?

Here you can find some snippets of the configuration

riva-api (pod) partial definition

apiVersion: apps/v1
kind: Deployment
metadata:
  name: riva-api
  namespace: riva
  labels:
    app: riva-api
    release: riva-api
spec:
  replicas: 2
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
  selector:
    matchLabels:
      app: riva-api
      release: riva-api
  template:
    metadata:
      labels:
        app: riva-api
        release: riva-api
    ...
    spec:
      ...
      containers:
        - name: riva-api
          image: nvcr.io/nvidia/riva/riva-speech:2.14.0
          ...

riva-api-online definition

apiVersion: v1
kind: Service
metadata:
  name: riva-api
  namespace: riva
spec:
  ports:
      ...
  selector:
    app: riva-api
    release: riva-api

Start with the Python entry point riva.client.ASRService(auth) and the Kubernetes Deployment and Service definitions included in the report. Determine whether the client reuses connections and whether that explains the observed pod imbalance; done means documenting a confirmed cause or the missing evidence needed to reproduce it.