How to check Total usage of RAM in Grafana in Multinode

Using the Linux monitoring Grafana dashboard General /Kubernetes / Compute Resources / Namespace (Workloads) 

that is showing total memory allocation in a sever, by default, you cannot switch between nodes (build/query)  and check the total load of Build or Query servers separately.

Solution:

1 Edit the dashboard

2. Add new Variable 

3.  see settings

query:   label_values(kube_node_info, node)

4. Edit Memory Usage Widget

5. add filter by node

node=~"$node"

Now you should be able to switch between nodes