flame graph shows hotspot for reading from producer events

[ORESoftware]

Description

the code is like:

    go func(i int) {
        //
        for e := range producer.Events() {
          //
          switch ev := e.(type) {
      
          case *kafka.Message:
            if ev.TopicPartition.Error != nil {
              vbl.Stdout.Warn(vbl.Id("bd9932dd-11ea-43ed-a7dc-c6e25aa33e73"), e)
              createNewProducer(i)
            }
            break; // break out of switch not loop
      
          case *kafka.Error:
            // Handle general errors, including possible disconnection
            vbl.Stdout.Warn(vbl.Id("2ea64bc1-b99a-4999-b8fb-1512e6dea09b"), e)
            createNewProducer(i)
            break; // break out of switch not loop
      
          case kafka.Error:
            // Handle general errors, including possible disconnection
            vbl.Stdout.Warn(vbl.Id("d5982db1-0af9-4b82-b058-4a5d272e6e29"), e)
            createNewProducer(i)
            break; // break out of switch not loop
      
          }
        }
      }(i)

How to reproduce

the flame graph was like this:

see the center - kafka.NewProducer.func5