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How do I interpret the memory usage returned by "kubectl top node". E.g. if it returns:
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY% ip-XXX.ec2.internal 222m 11% 3237Mi 41% ip-YYY.ec2.internal 91m 9% 2217Mi 60%
By comparison, if I look in the Kubernetes dashboard for the same node, I get: Memory Requests: 410M / 7.799 Gi
![[1]](https://i.stack.imgur.com/uz0ZS.png)
How do I reconcile the difference?
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Each node in your cluster must have at least 300 MiB of memory. A few of the steps on this page require you to run the metrics-server service in your cluster. If you have the metrics-server running, you can skip those steps. If the resource metrics API is available, the output includes a reference to metrics.k8s.io .
Kubernetes uses memory requests to determine on which node to schedule the pod. For example, on a node with 8 GB free RAM, Kubernetes will schedule 10 pods with 800 MB for memory requests, five pods with 1600 MB for requests, or one pod with 8 GB for request, etc.
kubectl top node is reflecting the actual usage to the VM(nodes), and k8s dashboard is showing the percentage of limit/request you configured.
E.g. Your EC2 instance has 8G memory and you actually use 3237MB so it's 41%. In k8s, you only request 410MB(5.13%), and have a limit of 470MB memory. This doesn't mean you only consume 5.13% memory, but the amount configured.
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits --------- ---- ------------ ---------- --------------- ------------- default kube-lego 20m (2%) 0 (0%) 0 (0%) 0 (0%) default mongo-0 100m (10%) 0 (0%) 0 (0%) 0 (0%) default web 100m (10%) 0 (0%) 0 (0%) 0 (0%) kube-system event-exporter- 0 (0%) 0 (0%) 0 (0%) 0 (0%) kube-system fluentd-gcp-v2.0-z6xh9 100m (10%) 0 (0%) 200Mi (11%) 300Mi (17%) kube-system heapster-v1.4.0-3405140848-k6cm9 138m (13%) 138m (13%) 301456Ki (17%) 301456Ki (17%) kube-system kube-dns-3809445927-hn5xk 260m (26%) 0 (0%) 110Mi (6%) 170Mi (9%) kube-system kube-dns-autoscaler-38801 20m (2%) 0 (0%) 10Mi (0%) 0 (0%) kube-system kube-proxy-gke-staging-default- 100m (10%) 0 (0%) 0 (0%) 0 (0%) kube-system kubernetes-dashboard-1962351 100m (10%) 100m (10%) 100Mi (5%) 300Mi (17%) kube-system l7-default-backend-295440977 10m (1%) 10m (1%) 20Mi (1%) 20Mi (1%) Here you see many pods with 0 request/limit means unlimited, which didn't count in k8s dashboard but definitely consume memory.
Sum up the memory request/limit you'll find they match k8s dashboard. 
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