Distributed Computing

• Intro
  • What is distributed computing? [Buyya, vol 2, p. 249]
  • What is a distributed system?
  • Comparison between:
    • network computing
    • distributed computing
    • cluster computing
    • parallel computing
• Theoretical distributed computing
  • Process algebra
  • Pi-calculus
• Erlang
  • Designed for concurrent distributed computing
  • Invoking functions: Module:Function(Arguments)
  • Defining functions:
     foo( X ) -> X1;
     foo( Y ) -> Y1.
  • SSA
  • Pattern matching
    • Empty variable is bound
    • Bound variable is matched
  • Modules
  • Lists and tuples
  • Dictionaries (finite maps) [Erlang, 4.4]
• Concurrency
  • Mutual exclusion
    • Token passing
  • Synchronization
    • Rendezvous points
  • Deadlocks
  • Concurrent objects
• Distributed objects
  • Introspection (or object capability publication)
• Message passing
  • Data marshaling (serialization/deserialization)
• RPC
• Promises [Erlang, 11.5]
  • Easy to implement using concurrent process
• Distributed shared memory
  • Group communication (process groups; multicasting [Erlang, 11.6])
  • Tuple spaces [Buyya, vol 2, Ch9]
    • Tuple reading uses unification pattern matching
• Agent computing
  • Migratory processes can be moved after they have started
  • Problem of message chasing an agent
• Parallel evaluation [Erlang, 11.10]
  • Parallel map
• Load balancing
  • Erlang: statistics(run_queue).
  • Adaptive load distribution [Erlang, 11.8]
• Persistence
  • Erlang: ``dets'' library
• Clusters
  • Heirarchies of groups