Techniques for identifying network congestion and adapting network performance to relieve the network congestion are described. As described, a network element such as a switch reports network congestion indicators such as link level control frames to a network controller. The network controller uses the network congestion indicators reported from the network elements to identify congestion points, data traffic, and data flows experiencing congestion at a network level. The network controller then determines optimized control parameters for the network in order to reduce or alleviate the congestion at the congestion points.