1. Grid Computing – Introduction Sathish Vadhiyar

2. Generic Grid Architecture/Components Resource Layer High speed networks and routers Computers Data bases Online instruments Service Layers User Portals Authentication Scheduling & Co- Scheduling Naming & Files Events Grid Access & Info Problem Solving Environments Application Science Portals Resource Discovery & Allocation Fault Tolerance Software

3. OK, I have built some software. Is mine a Grid software? Ian Foster’s three-point checklist: 1. coordinates resources not subject to centralized control 2. using standard, open, general-purpose protocols and interfaces 3. to deliver non-trivial qualities of service

4. Some Myriad Definitions  “Coordinated resource sharing and problem solving in dynamic, multi-institutional virtual organizations”  “Anatomy of the grid – highly flexible sharing relationships, sophisticated and precise levels of control over use of shared resources, sharing of varied resources, diverse usage modes.”  “Controlled sharing – not free access”  “Infrastructure enabling integrated, collaborative use of resources”  “Sharing resources can vary dynamically vary over time”  More colorful definitions keep coming  Common keywords: Coordinated, shared, multi-institutions, controlled, usage, collaboration

5. Differences with Other Technologies  Enterprise-level distributed computing – limited cross-organizational support  Current distributed computing approaches do not provide a general resource-sharing framework that addresses Virtual Organization (VO) requirements.  WWW – just client-server. Lacks richer interaction models  Technologies like CORBA, Java, DCOM – single organization, limited scope  Some of the Grid techniques complement existing techniques.

6. Grids vs Conventional Distributed Computing (Nemeth and Sunderam)  Distributed Computing  Virtual Pool of nodes  Set of nodes static. Users have login access. They explicitly know about nodes  VM constructed out of a priori knowledge  Resource assignment implicit  Resource owning  Grid Computing  Virtual Pool of wide range of resources  Set of nodes static/dynamic. Resources dynamic and diverse – can vary in number, can vary in performance  Difficult for user to get a priori knowledge  User abstraction at resource layers  Resource sharing  Apps. – resource requirements more than can be solved on machines “owned”

7. Continued

8. Nemeth and Sunderam

9. Motivating examples

10. SETI@home  To search new life and civilizations  Use individual computers’ idle time through running SETI@home screen saver  Screen savers retrieves data, analyzes and reports results back to SETI project  Looking for extra-terrestrial signal over a 12- second period  Each work unit takes 10 to 50 hours on an average computer – 2.4 to 3.8 trillion floating point operations

11. Steps and Statistics Data collected from Arecibo telescope in Puerto Rico onto tapes and shipped to SETI@home lab in UC, Berkeley. Break tapes -> work units -> given to users Find candidate signals reported from users Other steps: Checking data integrity Removing radio frequency interference (RFI) Identify final candidates Statistics: 208,174,383 work units 1,261 tapes Statistics from 1999-2004 Total Users5054812 Results received1459999962 Total CPU time1988719.151 years Floating Point Operations 5.278185e+21 Average CPU time per work unit 11 hr 55 min 56.3 sec Images and statistics from SETI web site

12. Climateprediction.net  Forecast climate in 21 st century  3 steps – explore current model, validate against past climate, forecast 21 st century climate  Different models (in terms of initial conditions, forcing [volcanoes, solar activity etc.], parameters [approximations or ranges of fixed values in the model. E.g. ice size in ocean, friction between different ocean layers]) distributed to different users  Massive ensemble experiment From climateprediction.net

13. Steps ExperimentGoalMethodology 1 Explore model sensitivity to parameters Identify suitable ranges of parameters. Each simulation includes 3 phases: Calibration (15yrs) Pre-industrial CO 2 run (15yrs) Double CO 2 run (15yrs) 2 Simulation of 1950- 2000 Assess model skill by making a probability based forecast of the past climate. Run the model with a range of initial conditions and parameters for the period 1950-2000. Compare model outputs with observations to assess how well the model performs. 3 Simulation of 2000- 2100 Make a probability based forecast of future climate. Run the model with a range of initial conditions, forcings and parameters for the period 2000-2100. From climateprediction.net

14. Prime number generation - GIMPS  Finding Mersenne prime numbers – 2 P -1  GIMPS is to find largest known Mersenne prime numbers  41 st Mersenne prime found recently - 2 24,036,583 -1 with 7,235,733 decimal digits !!!  GIMPS found seven  For mostly fun  1000s of Pentium PCs involved. Setup similar to SETI@home  PCs do primality tests

15. Other @home Projects  genome@home – designing new genes that form working proteins in cells. To study protein evolution. Individual PCs design protein sequences  folding@home – to study why proteins fold/misfold. Each PC simulates a particular kind of protein folding  evolution@home – to understand and simulate evolution  Compute-against-cancer – to study cancer cells and to design new cancer drugs  FightAids@home – screen millions of candidate drug compounds  Distributed.net – cryptography, secret key challenges  More can be found in http://boinc.berkeley.edu/projects.php

16. The Telescience project  Grid for remote accessing microscopes, data analysis and visualization  To study complex interactions of molecular and cellular biological structures and hence understand brain diseases  Interactively steer a 400,000-volt electron microscope at UC San Diego From TeleScience web site

17. References  http://www.globus.org/research/papers/chapter2.pdf http://www.globus.org/research/papers/chapter2.pdf  What is the Grid? A three point checklist. Ian Foster. GRIDToday, July 20, 2002.  The Anatomy of the Grid: Enabling scalable virtual organizations. I. Foster, C. Kesselman, S. Tuecke. IJSA. 15(3), 2001.  A Complete History of the Grid. Dr. Rob Baxter. Pdf Pdf  Zsolt Nemeth, Mauro Migliardi, Dawid Kurzyniec and Vaidy Sunderam. A comparative analysis of PVM/MPI and computational grids. In EuroPVM/MPI 2002.  Zsolt Nemeth and Vaidy Sunderam. A comparison of conventional distributed computing environments and computational grids. ICCS 2002.  Zsolt Nemeth and Vaidy Sunderam. A formal framework for defining grid systems. CCGrid 2002.