Software monitoring and debugging using compressed signature sequences

Signature based error detection techniques (e.g. the application of watchdog processors) can be easily extended to support software debugging. The run-time sequence of signatures is stored in an extension of the traditional checker. As the signatures identify the states of the program, a trace of the statements executed by the checked processor is available. The signature buffer can be efficiently utilized if the signature sequence is compressed. In the paper, two real-time compression methods are presented and compared. The general method uses predefined dictionaries, while the other one utilizes the structural information encoded in the signatures.