Grid Basics

1
Grid Basics

• Adarsh Patil
• http//www.adarshpatil.com/

2
What is Grid ?

• It is a volatile heterogeneous distributed
  system.
• It is all about sharing resources.
• It integrates all the heterogeneous resources
  that are spread across multiple administrative
  domains (educational institutions, offices,
  industries) across the world.
• It gives transparent/collaborative access to
  these resources and has distributed Job
  management system.
• It gives a feeling of Desktop supercomputing -
  means you are sitting in front of your desktop
  but you are connected to supercomputer.
• Grid grows and shrinks dynamically. There is
  nothing as such you have a static set of
  resources which we call as Grid.
• Cluster is not a Grid.

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What we mean by Grid Resources?

• PCs, Desktops, Workstations, Clusters, Software's
• Cluster of Clusters, Clusters of workstations,
  Piles of PCs
• Storage elements
• Mainframes, Supercomputers
• Visualization Instruments
• Collaborative Scientists and end users
• Applications
• (we may note here that resources involved in Grid
  are heterogeneous. For example different type
  of processors Pentium, AMD, PowerPC)

4
Why do we need to build Grid?

• To integrate and aggregate affordable(PC,Desktop,P
  rinters) and unaffordable (clusters,supercomputers
  ,mainframes,giant telescope etc) resources
• To provide high throughput
• To build and harvest collaborative boundaries
  across various communities in research.
• To give the user feeling of using a most powerful
  computer.
• Make fruitful use of the underlying resources and
  make it as a commodity

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Difference between Grid and Cluster
Characteristics Grid Cluster
System Heterogeneous (Pentium, AMD, PowerPC, Different Operating systems, Multiple owners) Homogeneous (only one kind of processor)
Single system Image No Number of autonomous systems Yes
Job Management System Distributed Centralized
Number of Nodes Ranges from 10s to millions Ranges from 10 to 100k
Fault Tolerance Scheduling Security Everything is distributed, concept of Local resource managers and Resource brokers Centralized scheduling, Fault Tolerance and security.
Software's used Mixture of Open Source and Proprietary Mostly Open Source Software's
Transparent Access It gives transparent access to whatever resources connected. Only access to the nodes of the Cluster and its attached storage.
Computing It is High Throughput Computing (HTC) It is High Performance Computing
Availability Highly Volatile, resource join and leave. No guarantee of quality of Service Highly Available . Good quality of service
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How can we build a Grid?

• This question has answers within itself . With
  respect to Grid this question means How do we
  take part in the Grid?
• Or
• How do we contribute to the Grid ?
• Or
• How to we use the Grid?
• Grid is a social being.
• Grid is analogous to Electricity Grid. Now if you
  ask How do we build Electricity Grid?
• Answers may be
• Connect to an existing Grid and use it (as a
  user) and contribute (as a resource).
• Build a grid using the existing resources using
  Grid toolkits , Core Middleware's, User Level
  Middleware's.
• Getting connected is being part of the Grid.

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Some Terminology Basics

• Middleware Resource Broker Resource Manager .
• Local Resource Manager - the one which is
  installed on a standalone PC / Node.
• Core Level Middleware - the one which controls
  Local Resource Managers.
• Grid Computing large scale Distributed
  Computing
• Grid computing superset of Cluster computing,
  Utility computing, On-demand computing,
  Metacomputing, P2P computing.
• Testbed - its an infrastructure built out of
  commodity or proprietary hardware / software to
  test your research ideas, experiments and
  activities. Example Practice court for playing
  tennis or squash.
• Virtual Organizations A community of users
  having common research interests and testbed
  supporting their interests. For Example a group
  of physicists , a group of chemists , a group of
  doctors, a group of computer scientists. Each of
  these groups forms a Virtual Organization (VO).
• Grid has no standard definition. Everyone has
  their own definition of Grid. So before jumping
  into what a person/company says its big into Grid
  Computing, get to know their definition of Grid.
• Please keep in mind the basic of everything
  remains the same but they change the name and
  attach new letters/words to it
• Well future is Grid

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Credits / Acknowledgements

• To all the authors/users/administrators/researcher
  s of the Grid Community
• Please mail me if you want to make changes or
  have any questions
• Google and Live are your friends