Add comments on ephemeral zk nodes created by cache servers.
Add comments on ephemeral zk nodes created by cache servers.

jam2in/arcus-misc,jam2in/arcus-misc,naver/arcus-misc,naver/arcus-misc,naver/arcus-misc,naver/arcus-misc,jam2in/arcus-misc,naver/arcus-misc,naver/arcus-misc,jam2in/arcus-misc,jam2in/arcus-misc,naver/arcus-misc,jam2in/arcus-misc,jam2in/arcus-misc,naver/arcus-misc,jam2in/arcus-misc