DATA PROCESSING SYSTEM AND METHOD

A method, system and computer program for modifying an executing application, comprising monitoring the executing application to identify at least one of a hot load instruction, a hot store instruction and an active prefetch instruction that contributes to cache congestion; where the monitoring identifies a hot load instruction, enabling at least one prefetch associated with the hot load instruction; where the monitoring identifies a hot store instruction, enabling at least one prefetch associated with the hot store instruction; and where the monitoring identifies an active prefetch instruction that contributes to cache congestion, one of disabling the active prefetch instruction and reducing the effectiveness of the active prefetch instruction.