Integrated graphical user interface for the back-end software sub-system

The ATLAS data acquisition and Event Filter prototype '-1' project was intended to produce a prototype system for evaluating candidate technologies and architectures for the final ATLAS DAQ system on the LHC accelerator at CERN. Within the prototype project, the back-end sub-system encompasses the software for configuring, controlling and monitoring the data acquisition (DAQ). The back-end sub-system includes core components and detector integration components. One of the detector integration components is the Integrated Graphical User Interface (IGUI), which is intended to give a view of the status of the DAQ system and its sub-systems (Dataflow, Event Filter and Back-end) and to allow the user (general users, such as a shift operator at a test beam or experts, in order to control and debug the DAQ system) to control its operation. The IGUI is intended to be a Status Display and a Control Interface too, so there are three groups of functional requirements: display requirements (the information to be displayed); control requirements (the actions the IGUI shall perform on the DAQ components); general requirements, applying to the general functionality of the IGUI. The constraint requirements include requirements related to the access control (shift operator or expert user). The quality requirements are related to the portability on different platforms. The IGUI has to interact with many components in a distributed environment. The following design guidelines have been considered in order to fulfil the requirements: use a modular design with easy possibility to integrate different sub-systems; use Java language for portability and powerful graphical features; use CORBA interfaces for communication with other components. The actual implementation of Back-end software components use Inter-Language Unification (ILU) for inter-process communication. Different methods of access of Java applications to ILU C++ servers have been evaluated (native methods, ILU Java support, Java IDL). Finally Java IDL was chosen, having as main advantage the independence of CORBA implementation. The IGUI reads the list of partitions from the Inter Process Communication (IPC) server and the user can select one of them. In interaction with the Resource Manager server the type of the access control is decided. The run control and data-flow configurations are read from the configuration database. The information about the sub-systems or components status (run control status, lists of Process Manager agents and processes, Data-Flow modules statistics) is read from the Information Service (IS) or is automatically obtained using the IS notification mechanism. The run parameters can be set by the user and are stored in the Information Service server. Through the IGUI the user can send commands to the Run Control main components (DAQ Supervisor and Root Controller). The user can send commands to the MRS (to change the filter or subscription criteria, to set the log control). The IGUI can be a client of the Process Manager, allowing to start auxiliary processes (monitoring tasks, bookkeeping tasks, etc). IGUI is designed as a Java application (JFrame). On the left side of the frame the Main Commands and below some major Run Parameters are displayed, such as run and event numbers. On the right side can be chosen different Panels: Run Parameter panel, showing all the run parameters and allowing user to set them; Run Control panel (tree and status for each controller with the possibility to send commands to a particular controller); DAQ Supervisor panel (DAQ Supervisor expert commands); Process Manager panel (list of PMG agents and processes); MRS panel; Data Flow panel (data flow configuration and parameters). Other panels could be added, displaying the status of other DAQ components or sub-systems. On the bottom of the main frame there is a MRS message display panel, showing all the received MRS messages. (authors)