A bug collapsing the whole service mesh

I am preparing a demo for the features of Knative and Istio with IBM CloudPak for Application on top of OpenShift Container Platform (OCP) 4.2. Everything went smoothly, the Knative service is able to scale down to zero pods and activate upon traffic comes in automatically until I turned on the tracing capability and visualizing the traffic with Kiali.

1. Turn on Kiali