1. A method implemented by a computing device to, automatically and without user intervention, determine a root cause of a performance issue in a software defined networking (SDN) network using flow statistics maintained by a plurality of hosts in the network, the computing device coupled to a network monitoring system that collects real-time network and cloud metrics in the network, the method comprising: receiving a request to perform a root cause analysis (RCA) for a first flow in the network that is experiencing a performance issue; obtaining, from the network monitoring system, flow path information for flows in the network; obtaining, from the network monitoring system, flow statistics for the flows in the network, wherein the flow statistics are collected by the network monitoring system from the plurality of hosts, and wherein the flow statistics are end-to-end flow statistics maintained by the plurality of hosts for a plurality of end-to-end connections, each end-to-end connection being between one of the plurality of hosts and one or more other hosts in the network; executing an RCA algorithm for the first flow to determine a root cause of the performance issue based on the obtained flow path information and the obtained flow statistics; and configuring, using machine learning, the computing device to determine, at a later time, that the network is experiencing a subsequent performance issue without the computing device having to receive a request to perform an RCE responsive to the subsequent performance issue and without the computing device having to access the flow statistics for the flows based on the determined root cause of the performance issue.