The P-GRADE Portal PDF E-mail
A P-GRADE Portal ( installation has been set up for the international GILDA training infrastructure in December 2006. The environment serves as a demonstration, dissemination and learning environment for everybody who is interested in the usage and capabilities of GILDA, the EGEE Grid middleware and the P-GRADE Portal itself. During the roughly one year the GILDA P-GRADE Portal has been used during every mayor EGEE Induction, EGEE Application Developer and ICEAGE events. The GILDA P-GRADE Portal is P-GRADE Portal 2.5 installation being connected to the GILDA training infrastructure. It provides graphical environment to perform certificate management, job submission, file transfer, information system browsing, application monitoring on GILDA, eliminating the sometimes cumbersome and hard to memorize commands from the learning curve. As a result the learning time required for Grids can be significantly shortened by the tool. Besides providing graphical interfaces for GILDA middleware services, the GILDA P-GRADE Portal also contains high level tools that extend the capabilities of gLite. Workflows and parameter studies can be defined and managed by the graphical editor the integrated workflow manager components.
Attendees of P-GRADE courses are provided with pre-defined exercises that introduce the general concept of parallel Grid application development and use the EGEE middleware to demonstrate them in practice. These exercises stress gLite middleware services and they are formulated as data parallel parametric studies, functional parallel workflows or some combination of these two. Based on the examples students can understand and distinguish the generic concepts of Grid applications from implementation details specific to a gLite VO or on a Globus VO. (P-GRADE Portal is also compatible with Globus middleware based Grids, however this is not used in the GILDA P-GRADE Portal installation.) We can declare that P-GRADE courses are very beneficial for attendees.
On the other hand, such events are prosperous for the developers of P-GRADE and gLite too. As tutors meet existing and potential new Grid users who are committed to understanding the capabilities and limitations of Grid systems they can easily collect feedback. Feedbacks collected during training are very valuable in order to set priorities and lay down roadmaps for future developments. Consequently, tutors of P-GRADE Portal sessions take extra care to take note of the experience of every course, to categorize and then to forward these notes to appropriate Grid developer and operator groups. In order to demonstrate the maturity of Grid and the benefits of the technology we use real life applications during P-GRADE Portal tutorials wherever possible. However, it is necessary to decrease the size of those applications in order to fit them into the time and resource constraints of the events. This is typically achieved by reducing the size of the input data sets – resulting shorte execution times and smaller resource demands – or dropping some application components. An urban traffic simulator and analyzer workflow is a good example for this. The application was originally developed by the University of Westminster in P-GRADE to analyze the density of cars on the roads of Manchester. Since 2006 it is used during P-GRADE Portal events to demonstrate the concept of data driven workflows and basic steps of workflow management. As the original workflow was running for about an hour the input data set had to be reduced and now it finishes in about 10 minutes on GILDA thus suitable for training purposes. Although students work more eagerly on exercises that are based on real life case studies, sometimes setting up exercises from scratch solely for the sake of training is inevitable. This is the situation when such capabilities of P-GRADE must be demonstrated that are new, or simply not used by any production application yet. As P-GRADE aims to serve as a general Grid application developer and executor environment its new features target potential application classes. Meanwhile other Grid tools are typically designed for one particular experiment, most of the P-GRADE features are not used right after they become part of a release, their take up by Grid communities take some time until new features become known and understood. Some artificial exercises shorten this take up period focusing onto such new features and putting them into theoretical but possible use case scenarios.
The GILDA P-GRADE Portal provides permanent service that anybody can access any time. Having the training environment and infrastructure publicly available all the time is very beneficial, as in this way participants of organized events can continue their P-GRADE studies after the course. These people can stay in the same environment and can reuse applications that they designed during the tutorial. However, as the certificates they use during tutorials expire on the same day (or within a few days) these people must obtain new GILDA certificates and must register to the GILDA VO again. Even if GILDA provides lightweight mechanisms through its web to accomplish these steps, users loose a few days and must invest a few hours extra work just to get GILDA access again.
Tutorial certificates with extended lifetime or some simplified GILDA registration procedure could address this issue. (For example in a simplified GILDA registration procedure the user could obtain a GILDA certificate, GILDA VO membership and user accounts on GILDA UI, GENIUS and PGRADE Portal in a single step, filling out only one web form).
Last Updated on Tuesday, 03 March 2009 17:41