Xab: a tool for monitoring PVM programs

Xab is a run time monitoring tool for parallel virtual machine (PVM) programs. Xab gives the user direct feedback as to what PVM functions his or her program is performing. In its most simple form, this feedback is displayed in a window. The approach of real time monitoring is particularly apropos in a heterogeneous multiprogramming environment. Differences in computation and communication speeds here are due both to heterogeneity and external CPU and network loads. Monitoring can help give the user insight into how a program is behaving in such an environment. Xab is a continuing research project. The author discusses several related research projects, the current version of Xab, and the future development of the Xab tool.<>