OcAgentMetricsExporter Channel ManagedChannelImpl was not shutdown properly

[yiyijin]

Please answer these questions before submitting a bug report.

What version of OpenCensus are you using?

0.23

here are the dependencies configure:

"io.opencensus:opencensus-api:0.23.0",
  "io.opencensus:opencensus-impl:0.23.0",
  "io.opencensus:opencensus-exporter-metrics-ocagent:0.23.0", // uses gRPC version 1.19
  "io.opencensus:opencensus-exporter-trace-ocagent:0.23.0",
  "io.netty:netty-tcnative-boringssl-static:2.0.20.Final" // this is the compatiable version with gRPC

What JVM are you using (java -version)?

java version "1.8.0_192"

What did you do?

In our application, we use opencensus library to collect metrics, and configured using OcAgentMetricsExporter. The application and oc-agents are both running in the same kubernetes cluster.

OcAgentMetricsExporterConfiguration configuration = OcAgentMetricsExporterConfiguration.builder()
          .setEndPoint(metricsExporterEndpoint)
          .setServiceName(serviceName)
          .setUseInsecure(true)
          .build();
        OcAgentMetricsExporter.createAndRegister(configuration);

occasionally we see the following Exception:

io.grpc.internal.ManagedChannelOrphanWrapper$ManagedChannelReference cleanQueue
SEVERE: *~*~*~ Channel ManagedChannelImpl{logId=1, target=oc-agent.opencensus:55678} was not shutdown properly!!! ~*~*~*
    Make sure to call shutdown()/shutdownNow() and wait until awaitTermination() returns true.
java.lang.RuntimeException: ManagedChannel allocation site
	at io.grpc.internal.ManagedChannelOrphanWrapper$ManagedChannelReference.<init>(ManagedChannelOrphanWrapper.java:94)
	at io.grpc.internal.ManagedChannelOrphanWrapper.<init>(ManagedChannelOrphanWrapper.java:52)
	at io.grpc.internal.ManagedChannelOrphanWrapper.<init>(ManagedChannelOrphanWrapper.java:43)
	at io.grpc.internal.AbstractManagedChannelImplBuilder.build(AbstractManagedChannelImplBuilder.java:512)
	at io.opencensus.exporter.metrics.ocagent.OcAgentMetricsExporterWorker.connect(OcAgentMetricsExporterWorker.java:107)
	at io.opencensus.exporter.metrics.ocagent.OcAgentMetricsExporterWorker.run(OcAgentMetricsExporterWorker.java:83)
	at java.lang.Thread.run(Thread.java:748)

Question:

1. does this impact the metrics send to oc-agent? meaning will the metrics get lost due to this error?

2. how to fix this issue?