Discretionary, Adaptive Concurrency

Carl Hewitt

Discretionary, adaptive concurrency is the ability to size computations to fit available resources in terms of demand and available capacity (e.g. cores).

ActorScript^TM is a new programming language that has been developed to express discretionary, adaptive concurrency as follows:

• Universality
  
  • Everything in the language is accomplished using message passing including the very definition of the language itself.
  • Directly express discretionary push and pull concurrency
  • Functional and Logic Programming are integrated into general concurrent programming.
  • Programs do not expose low-level implementation mechanisms such as threads, tasks, locks, cores, mail boxes,inheritance class hiearchies, etc. Messages can be directly communicated without requiring indirection through channels, queues, pipes, ports, etc.
  • Program resource control of energy, processing, storage, and communications using sponsors.
  • Binary XML and JSON are data types
  • Applications cannot directly harm each other.
• Efficiency
  
  • Allow execution to be dynamically adjusted for system load and capacity (cores)
  • Minimize latency along critical paths
  ActorScript attempts to achieve the highest level of performance, scalability, and expressibility with a minimum of primitives.

  Further reading:

  ActorScript^TM extension of C#^TM, Java^TM, and Objective C^TM : discretionary, adaptive concurrency for privacy-friendly, client-cloud computing” ArXiv 1008.2748

  Actor Model for Discretionary Adaptive Concurrency ArXiv. 1008.1459

  Slides:

  There is no downloadable version of the slides for this talk available at this time.

  About the speaker:

  Carl Hewitt's doctoral dissertation included a design for Planner, the first programming language based on procedural plans invoked using pattern-directed invocation from assertions and goals. Planner was influential in the development of both logic programming and object-oriented programming. He is also known for his work on the Actor model of concurrent computation, which influenced the development of the Scheme programming language and the Π calculus, and served as a inspiration for several other programming languages. His publications also include contributions in the areas of open information systems, organizational and multi-agent systems, logic programming, concurrent programming languages, inconsistency robustness, and client-cloud computing. Hewitt's Erdős number is 3 (by two different co-authors).

  His recent work is published in the electronic journal ArXiv and can be downloaded at:
  

  http://arxiv.org/find/cs/1/au:+Hewitt_C/0/1/0/all/0/1

  Contact information:

  Carl Hewitt