Net-dbx: A Java powered tool for interactive debugging of MPI programs across the Internet

Abstract

This paper describes Net-dbx, a tool that utilizes Java and other WWW tools for the debugging of MPI programs from anywhere in the Internet. Net-dbx is a source level interactive debugger with the full power of gdb augmented with the debug functionality of LAM-MPI. The main effort was on a low overhead but yet powerful graphical interface that would be supported by low bandwidth connections. The portability of the tool is of great importance as well because it enables us to use it on heterogeneous nodes that participate in an MPI multicomputer. Both needs are satisfied a great deal by the use of Internet Browsing tools and the Java programming language. The user of our system simply points his browser to the URL of the Net-dbx page, logs in to the destination system, and starts debugging by interacting with the tool just like any GUI environment. The user has the ability to dynamically select which MPI-processes to view/debug. A working prototype has already been developed and tested successfully.