Application of remote debugging techniques in user-centric job monitoring

With the Job Execution Monitor, a user-centric job monitoring software developed at the University of Wuppertal and integrated into the job brokerage systems of the WLCG, job progress and grid worker node health can be supervised in real time. Imminent error conditions can thus be detected early by the submitter and countermeasures can be taken. Grid site admins can access aggregated data of all monitored jobs to infer the site status and to detect job misbehaviour. To remove the last 'blind spot' from this monitoring, a remote debugging technique based on the GNU C compiler suite was developed and integrated into the software; its design concept and architecture is described in this paper and its application discussed.