AgendaCourse OverviewDistributed System BasicsMultiprocessor
Systems (Basic Architecture)Motivation behind Distributed
SystemsDistributed System Architecture TypesDistributed Operating
SystemDOS Issues
Text BookAdvanced Concepts in Operating Systems: Distributed,
Database and Multiprocessor Operating Systems, Tata McGraw Hill,
2001.
By
M. Singhal & N. Shivaratri
Reference Books R1: P. K. Sinha, Distributed Operating Systems
Pearson Education, 1998.R2: Andrew S Tanenbaum and Martin Steen,
Distributed Systems : Principles and Paradigms ISBN:
978-81-203-3498-4 R3: Distributed Systems-Concepts and Design by G.
Coulouris, AW
Plan of Study
Plan of Study
Distributed Systems A Distributed System is a collection of
independent computers that appears to its users as a single
coherent system [Tanenbaum] A Distributed System is a system having
several computers that do not share a memory or a
clockCommunication is via message passingEach computer has its own
OS+Memory[Shivaratri & Singhal]
Multiprocessor System Architecture TypesTightly Coupled
SystemsLoosely Coupled Systems
Tightly Coupled Systems Systems with a single system wide memory
Parallel Processing System , SMMP (sharedmemory multiprocessor
systems)
CPU
Shared memory
CPU
CPU
CPU
Interconnection hardware
Loosely Coupled SystemDistributed Memory Systems
(DMS)Communication via Message Passing
Distributed System Architecture TypesMinicomputer
ModelWorkstation ModelWorkstation Server ModelProcessor Pool
ModelHybrid Model
MINICOMPUTER MODEL
WORKSTATION MODEL
WORKSTATION SERVERMODEL
Processor Pool Model
Hybrid ModelBased upon workstation-server model but with
additional pool of processorsProcessors in the pool can be
allocated dynamicallyGives guaranteed response time to interactive
jobsMore expensive to build
Distributed OSA distributed OS is one that looks to its users
like an centralized OS but runs on multiple, independent CPUs. The
key concept is transparency. In other words, the use of multiple
processors should be invisible to the user. [Tanenbaum & Van
Renesse]
Issues Global knowledgeNamingScalabilityCompatibilityProcess
SynchronizationResource ManagementSecurityStructuring
