Global state monitoring can be applied in parallel applications in cluster environments to efficiently control execution of constituent processes. We present an application control method based on global predicate monitoring, used in a parallel system with partially synchronized computer clocks. Thanks to the clock synchronization, the global state construction can be done without big overhead. The proposed control method has been implemented in an enhanced P-GRADE graphical parallel program design system (PS-GRADE). As many irregular computational problems require sophisticated and unpredictable control actions, their implementations can benefit from the proposed control method. The Traveling Salesman Problem and adaptive integration -two irregular applications - have been implemented in PS-GRADE. Obtained results have shown, that the control by global predicate monitoring can lead to better parallel application performance and provides a convenient infrastructure for a programmer.