MELDing Multiple Granularities of Parallelism

We are developing an experimental programming language, MELD, that supports a range of concurrent styles by supporting multiple programming paradigms at multiple levels of granularity. MELD integrates three granularities of parallelism: macro dataflow among statements within a method or among methods for fine grain concurrency, synchronous or asynchronous message passing among local or remote objects for medium grain concurrency, and transactions for large grain concurrency among users

An Object Model for Shared Data

The classical object model supports private data within objects and clean interfaces among objects, and by definition does not permit sharing of data among arbitrary objects. This is a problem for certain real-world applications, where the same data logically belongs 10 multiple objects and may be distributed over multiple nodes on the network. Rather than give up the advantages of encapsulated objects in modeling real-world entities, we propose a new object model that supports shared data in a distributed environment. The key is separating distribution of computation units from information hiding concerns. We introduce our new object model, describe a motivating example from the financial services domain, and then present a new language, PROFIT, based on the model

Object-Oriented Programming Language Facilities for Concurrency Control

Concurrent object-oriented programming systems require support for concurrency control, to enforce consistent commitment of changes and to support program-initiated rollback after application-specific failures. We have explored three different concurrency control models -- atomic blocks, serializable transactions, and commit-serializable transactions -- as part of the MELD programming language. We present our designs, discuss certain programming problems and implementation issues, and compare our work on MELD to other concurrent object-based systems

Towards a Framework for Comparing Object-Oriented Systems

Choosing a suitable object-oriented system for a particular application domain is very hard, at least in part because the object-oriented research community has not yet converged on what is meant by "object-oriented system". In order to solve this selection problem, a comparison framework is proposed to evaluate a range of object-oriented systems. We then use this framework to consider three different systems, MELD, MARVEL, and VBASE, which represent several quite different design choices for object-oriented systems. We also show the advantages as well as disadvantages about such a framework, and discuss future extensions

Navigating the MeldC

This manual covers not only MeldC keywords, syntax, and currently, implemented features, but also a simple (and, one hopes, painless) introduction to some areas of computer science research that spurred creation of the language. This approach was taken so that readers who are not familiar with the peculiarities of operating systems theory, the object-oriented programming paradigm, and network communication might gain a quick overview of those subjects and be able to better appreciate MeldC‘s features. For the sake of style, these overviews are knitted into the discussions of keywords and syntax, so more educated readers be forewarned