scale kube_aws_iam_controller VPA dynamically

1. Replaces `memory_max` config-item with `memory` and sets the default to
a reasonable 50Mi.
2. Adds dynamic scaling relative to master instance size for `maxAllowed` in
the VPA.

Author: demonCoder95

cluster/config-defaults.yaml

@@ -417,7 +417,7 @@ metrics_service_mem_max: "4Gi"
 metrics_server_metric_resolution: "15s"
 
 kube_aws_iam_controller_cpu: "5m"
-kube_aws_iam_controller_mem_max: "1Gi"
+kube_aws_iam_controller_mem: "50Mi"
 
 kube_state_metrics_cpu: "100m"
 kube_state_metrics_mem_max: "4Gi"

cluster/manifests/02-kube-aws-iam-controller/deployment.yaml

@@ -34,10 +34,10 @@ spec:
         resources:
           limits:
             cpu: "{{.Cluster.ConfigItems.kube_aws_iam_controller_cpu}}"
-            memory: "{{.Cluster.ConfigItems.kube_aws_iam_controller_mem_max}}"
+            memory: "{{.Cluster.ConfigItems.kube_aws_iam_controller_mem}}"
           requests:
             cpu: "{{.Cluster.ConfigItems.kube_aws_iam_controller_cpu}}"
-            memory: "{{.Cluster.ConfigItems.kube_aws_iam_controller_mem_max}}"
+            memory: "{{.Cluster.ConfigItems.kube_aws_iam_controller_mem}}"
       tolerations:
       - key: node.kubernetes.io/role
         value: master

cluster/manifests/02-kube-aws-iam-controller/vpa.yaml

@@ -17,4 +17,11 @@ spec:
     containerPolicies:
     - containerName: kube-aws-iam-controller
       maxAllowed:
-        memory: {{.Cluster.ConfigItems.kube_aws_iam_controller_mem_max}}
+        {{ range $NodePool := .Cluster.NodePools }}
+        {{ if eq $NodePool.name "default-master" }}
+        # Scaling is relative to r6g.large (smallest master node)
+        # 0.014 -> 25m CPU, 0.003 -> 50Mi memory
+        cpu: {{ scaleQuantity ( instanceTypeCPU ( index .InstanceTypes 0 )) 0.014 }}
+        memory: {{ scaleQuantity ( instanceTypeMemory ( index .InstanceTypes 0 )) 0.003 }}
+        {{ end }}
+        {{ end }}