Control and Debugging of Distributed Programs Using Fiddle

TL;DR

Fiddle is a flexible distributed debugging platform that supports integrated testing and debugging of multi-threaded applications through layered interfaces and command interpretation.

Contribution

This paper introduces Fiddle's architecture and demonstrates how it supports integrated testing and debugging with a new tool, Deipa, for controlling distributed program execution.

Findings

Fiddle provides layered debugging interfaces for distributed applications.

Deipa enforces specific execution paths in distributed PVM programs.

A working example illustrates Fiddle and Deipa's debugging capabilities.

Abstract

The main goal of Fiddle, a distributed debugging engine, is to provide a flexible platform for developing debugging tools. Fiddle provides a layered set of interfaces with a minimal set of debugging functionalities, for the inspection and control of distributed and multi-threaded applications. This paper illustrates how Fiddle is used to support integrated testing and debugging. The approach described is based on a tool, called Deipa, that interprets sequences of commands read from an input file, generated by an independent testing tool. Deipa acts as a Fiddle client, in order to enforce specific execution paths in a distributed PVM program. Other Fiddle clients may be used along with Deipa for the fine debugging at process level. Fiddle and Deipa functionalities and architectures are described, and a working example shows a step-by-step application of these tools.