1. Distributed Computing CSC 345 – Operating Systems By - Fure Unukpo 1 Saturday, April 26, 2014

2. Outline Introduction Design and Architecture Client–server Three-tier Client–server Architecture N-tier architecture, clustered computing and peer-to-peer Communication and Synchronization Properties and Design goals Resource Sharing Scalability Performance and latency Availability and fault tolerance Transparency Concurrency Case Study - Folding@home Conclusion 2

3. Introduction Evolution of distributed computers Simple single core computers Simple Problems Complex Problems More Cores, Faster Processor Hardware Limit Reached More computers Distributed Systems 3

4. Distributed system consists of a set of independent computers, connected through a network and running a software that enables them to coordinate their activities and to share the resources of the system Appears as a single integrated unit to the user Computers close together or far apart geographically Individual computers have vary configurations 4

5. Design and Architecture Client–server N-tier architecture Clustered computing Peer-to-peer Three-tier Client–server Architecture 5

6. Communication & Synchronization Communication Remote Procedure Call (RPC) Proxy model Multilayer model Synchronization Cristian’s Algorithm Berkeley Algorithm Centralization Atomic Transactions 6

7. Properties and Design goals Resource Sharing Scalability Performance and latency Availability and fault tolerance Transparency Concurrency 7

8. Case Study Folding@home Project? 8

9. Case Study Biomedical Research in Stanford Since year 2000 Both CPU and GPU utilized Windows, Mac, Linux Computers 303, 238 computers 45.9 petaFLOPS PS3 (2007 – 2013) 15 million volunteers 100 million hours of Computation 9

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