When testing the results of
KUDU-1802 I saw that each query ran would result in 5 GetTableSchema requests to the Kudu master server. The request comes from each KuduClient.openTable call in the Impala frontend.
Ideally Impala would only call KuduClient.openTable once and then use the returned KuduTable object for the length of the query. That would result in 5x fewer remote RPC calls to the Kudu master server per query.