Erlang Programming

Chapter 11. Distributed Programming in Erlang

To write a fault-tolerant system, you need at least two computers^[27] and you need to distribute your program across them. Distributed systems lie at the heart of modern computing. In server-side programming, it is the exception rather than the rule to see a single computer performing a task of any difficulty; instead, a number of computers (or processors) will together provide a robust, efficient, and scalable platform upon which applications can be built.

Erlang distribution is built into the language, and from the user’s point of view, it can be completely transparent: processes are accessed by a pid, and this may equally well refer to a process on the local computer or a process on a system on the other side of the world. In this chapter, we will look at the theory behind distributed systems and see how it is applied to Erlang-based systems.

Distributed Systems in Erlang

The essence of distributed systems is to provide in a transparent way a service of some kind through a number of computers, processors, or cores linked together by a network. A service can be specific, such as the storage provided by a distributed filesystem or database, or more general, as in a distributed operating system that provides all the facilities of a general-purpose OS across a network of computers. Distribution can be seen in tightly coupled parallel processors, but more clearly in the loosely coupled grids of e-science systems. Erlang provides distributed ...