How could Karmada know CPU and memory value ?

[XMingG99]

As we know, when we run command kubectl get cluster member1 -o yaml --context=karmada-apiserver , we can get a describe of member1. In the describe, which have a field named resourceSummary, in resourceSummary, there have the info of CPU. How could Karmada get this value? By promethus?
resourceSummary: allocatable: cpu: "4" ephemeral-storage: 49805880Ki hugepages-1Gi: "0" hugepages-2Mi: "0" memory: 8147848Ki pods: "110" allocated: cpu: 850m memory: 190Mi allocating: cpu: "0" memory: "0"

[RainbowMango]

The cluster-status-controller would sync the resource from clusters.

[XMingG99]

ok, thank you

[xiaxinyu]

Sorry to interupt, I also am interesting in this quesiton.
For another questions, cloud karmada perceive the physical resource from hosts that used by clusters?
And How does karmada process where hosts on clusters haven't additional physical resouce when client is woking on deploying from karmada?