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arXiv · 0910.5046

Temporal Debugging using URDB

Ana Maria Visan·Artem Polyakov·Praveen S. Solanki·Kapil Arya·Tyler Denniston·Gene Cooperman
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Abstract

A new style of temporal debugging is proposed. The new URDB debugger can employ such techniques as temporal search for finding an underlying fault that is causing a bug. This improves on the standard iterative debugging style, which iteratively re-executes a program under debugger control in the search for the underlying fault. URDB acts as a meta-debugger, with current support for four widely used debuggers: gdb, MATLAB, python, and perl. Support for a new debugger can be added in a few hours. Among its points of novelty are: (i) the first reversible debuggers for MATLAB, python, and perl; (ii) support for today's multi-core architectures; (iii) reversible debugging of multi-process and distributed computations; and (iv) temporal search on changes in program expressions. URDB gains its reversibility and temporal abilities through the fast checkpoint-restart capability of DMTCP (Distributed MultiThreaded CheckPointing). The recently enhanced DMTCP also adds ptrace support, enabling one to freeze, migrate, and replicate debugging sessions.

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Ana Maria Visan, Artem Polyakov, Praveen S. Solanki, Kapil Arya, Tyler Denniston, Gene Cooperman. 2009-10-27. Temporal Debugging using URDB. https://arxiv.org/abs/0910.5046

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