Disclosed is a method for continuous in-line monitoring of data-centric traffic to guarantee application performance. The method includes, in each switch of a plurality of switches in a network fabric, grouping all packets entering each respective switch of the plurality of switches based on either 5-tuple applications or EPG based applications, collecting performance statistics at every hop in the network fabric across all flows in-line in a flow table maintained in each respective switch and periodically exporting the performance statistics to analysis module.