LCG Tier 2 and DOSAR

Pat Skubic

OU

Outline

• Introduction to LCG

• List of LHC Tier 2 Centers

• Status of ATLAS SW Tier 2

• Questions for Discussion

• Action Items?

                                                                                                                                                                 

Development Areas

• Applications

• Fabric

• Grid Deployment

• Grid Technology

• ARDA-A Realization of Distributed Analysis for LHC

Applications

                                                                                                                     

                                                                                                                                              

                                                   

                                                         

Grid Deployment Organization

Grid Technology Activities

• Overall Requirements

• Technology Tracking

• Middleware Development

• Middleware Recommendations

Overall Requirements

• Keep a clear view of the emerging requirements for the LHC computing including batch and interactive analysis. The HEPCAL document is the starting point for this.

• Track the grid activities within the experiments and help disseminate the experiences gained

• Disseminate the need for high quality infrastructure services and work towards their technical realization

• Work towards a systems architecture for grid technology to support the project

Technology Tracking

• Monitor closely the technology evolution and “put into practice” the technologies as they mature in production. Work with the experiments to perform structured tests will be required. This may also involve working with industry and other sponsored developments to prototype and test solutions as they emerge

• Study the system architecture issues as experience is gained in order to steer the technology evolution

Middleware Development• Seek strategic advice from the individuals driving

the multiple projects producing the core technologies

• Work towards one set of common and complementary projects encompassing the efforts underway. This involves participating in the plans for funding future projects

• Identify key developments that are required for the LHC computing grid that are not developed as part of existing projects and promote their development.

Middleware Recommendations

• Recommend a coherent technology suite to be deployed to regional centers. This has to be done taking into account the matching with the LHC requirements

• Develop a plan for the evolution of this suite as new products become available and as new technologies mature

• Work towards developing a long term support structure for the middleware technology

ARDA• The basic middleware development team.

Joint European-US team, part of EGEE project, but including participation from VDT.

• At least one team in each experiment, that takes part in adapting the analysis system of their experiment to use the basic middleware.

• Providers of common HEP tools, such as POOL, SEAL, ROOT, GANGA and PROOF.

• Users within experiments that will provide immediate feedback to the developers.

ARDA (con’t)

• Service providers from regional centers who will be involved in deploying early versions of the middleware and analysis systems.

• The participation of teams from other sciences, such as those participating in EGEE, is welcomed.

SW Tier 2 Status• Tier 2 Center

– ATLAS management selected OU, LU, UT-Arlington, as a Tier 2 Center (Southwest Tier 2 Center)

– Collaboration started on grid software development (PanDA)

– OCHEP linux cluster will be deployed this year• Efforts will be made to increase NSF funding

• Physics Analysis: OCHEP collaboration will begin on physics topics, building on Tevatron experience– b tagging

tagging

– top physics

– Higgs/SUSY searches

Production and Distributed Analysis (PanDA)

Questions for Discussion

Questions from Sergio

• How would we fit in the general structure of LCG?

• Will DOSAR VO become a distributed Tier 2 center?

• Which would be our associated Tier 1? Fermilab?• What should we do to comply with Atlas and

CMS requirements?• How will we share our resources between D0 and

LHC?

Should DOSAR collaborate with other Tier 2 Centers?

• CMS Tier 2C?

• Brazil Tier 2 Federation?

Should DOSAR participate in LCG software development or

deployment?

• Common ATLAS-CMS projects?

Should DOSAR software efforts be part of larger collaborations?

• OSG proposal?

• PanDA and DIRAC?

DIRAC- Distributed Infrastructure with Remote Agent Control

•Services: installed on high availability, centrally managed, servers •Agents: installed at various computing centres of institutes associated with the LHCb experiment

•Clients: available to end users to submit, monitor, and retrieve jobs

DIRAC (con’t)• It has been designed to be lightweight, robust, and scalable. This has

been achieved by using a service oriented architecture and utilizing existing software for key components: 99% of DIRAC is written in Python, which provides a high performance, object oriented scripting language for

rapid development, and maintenance. • MySQL database is used for persistency. Services make connections to

various DBs to manage job state, monitoring information, and meta-data

concerning grid files. • Condor ClassAds and Matchmaking are the basis of the scheduling

strategy. This makes the best match between an available resource and a

queued job. • Jabber Instant Messaging has been used to provide asynchronous, real-

time, fault-tolerant monitoring and control capabilities to DIRAC Agents,

Services, and Jobs.

Action Items

• To be decided after discussion