1. remove a blocking risk when kafka is down and the span channel is full 2. remove parentID when parentID is 0
1. remove a blocking risk when kafka is down and the span channel is full
2. remove parentID when parentID is 0

yzprofile/go-plugins,myodc/go-plugins,foxliu20/go-plugins,foxliu20/go-plugins,yzprofile/go-plugins,micro/go-plugins,micro/go-plugins