Perf-top not showing metrics

When I run

perf-top-linux --dashboard dashboards/ClusterOverview.json --logfile ~/perftop.log

I dont see any metrics. in the perftop log , I see

Failed to retrieve data for metrics. HTTP(S) response was:
        {"error":"Metrics Processor is not initialized. The reader has run into an issue or has just started."}

and when I do netstat I see

 netstat -plten |grep 9600
tcp6       0      0 :::9600                 :::*                    LISTEN      9003       24774060   16613/java

Any further steps to triage the issue

Hi gude.ravi,
Do you know if you have enabled https for the reader process. If so, can you try

perf-top-linux --dashboard dashboards/ClusterOverview.json --logfile ~/perftop.log  --endpoint https://localhost:9600

Can you also check if the reader process is running at all. You can run a sample command like the one below and see the response

curl -XGET http://localhost:9600/_opendistro/_performanceanalyzer/metrics?metrics=Latency,CPU_Utilization&agg=avg,max&nodes=all

                      or 
[if you have https enabled]

curl -k -XGET https://localhost:9600/_opendistro/_performanceanalyzer/metrics?metrics=Latency,CPU_Utilization&agg=avg,max&nodes=all