EGI Technical Forum

Job Summaries – Extended Event Info on Finished Jobs over L&B Notifications

Not scheduled

Lyon Conference Centre

Poster

Speaker

Mr Zdenek Sustr (CESNET)

Description

L&B notifications are a well-established tool used by user groups to monitor the progress of their jobs. In the original scenario, notifications were sent out any time the L&B server received an event matching pre-set criteria, saving the necessity to poll the server periodically for job status updates. Later the filters were extended so that only events resulting in a job state change were reported to users through notification messages. As of L&B version 3.0 (introduced with the EMI-1 release), OpenWire/STOMP-based Messaging was adopted as an alternative path to deliver L&B's notification messages alongside the legacy delivery path. There are user groups – especially those focusing on grid monitoring and grid traffic analysis – who may not necessarily need to receive individual updates as a job progresses (although many still do), but require most detailed knowledge of a job's history once it finishes. Among those, the Real Time Monitor (RTM) and the Grid Observatory are most prominent. Recently the L&B product team was approached by the Grid Observatory project to provide a feature just like that. That is why the notification functionality in L&B has been extended once more. When registering to receive notifications, users may indicate that they wish to receive a summary of all related events once a job reaches a terminal state. This combines naturally with standard notification functionality, so that users may opt to receive messages on every event, receive a summary once the job has finished, or both. From a technical standpoint, summaries are an extension of terminal-state notification messages. They can be dispatched over the Messaging infrastructure, or through the legacy service – both delivery paths support the functionality. With the help of detailed job summaries, grid traffic analysts or VO experts are able to reconstruct the goings on in the grid more precisely, and provide the community with a better picture of life within the grid.