After managing the vcenter for a few days, cpu and memory utilization are displayed “No data available”

Show as below:
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image

How can I fix it ?

same

Check that the 3 Capacity & Utilization server roles are enabled, and that you have enabled “All Clusters/Datastores” (or specified clusters/datastores) in the Configuration -> Settings -> Region -> C&U Collection tab.

Note that if you have many hundreds or thousands of VMs (especially VMware) then you’ll probably need to scale out the number of C&U collector workers and even appliances to gather the metrics in a timely manner (VMware realtime metrics expire after 1 hour on the vCenter).

You can check the performance of C&U collection using perf_process_timings.rb from here:

pemcg