Erlang OTP

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Joe Erlang had fault tolerance in his mind when he designed and implemented Erlang. He was the chief architect of the project which built Erlang/OTP.

Features of Erlang:
  • Concurrent
  • Scalable
  • Soft-Real Time
  • Distributed
  • Fault Tolerant

    Where all is Erlang used?
  • Telecom
  • Banking
  • E-Commerce
  • Instant Messaging
  • Computer Telephony

    What is OTP?
    OTP is set of Erlang libraries and design principles providing middle-ware to develop these systems.
    It includes its
  • own distributed database
  • applications to interface towards other languages
  • debugging
  • release handling tools

    Ericsson managed to get the nine 9's reliability in one of its product (99.9999999% reliability).

    Erlang is based on the following ideas:
  • Share Nothing
  • Pure message passing
  • Crash detection. Let it crash and recover principle

    Erlang processes are very lightweight. Erlang can have hundreds of thousands of processes.

    Garbage collection is also good. It can have thousands of independent heaps and all are garbage collected separately. So long-running applications will not stop responding when they perform garbage collection.

    Erlang server will never crash your OS. Erlang is made that way.

    Refactoring is a big trouble in Erlang. But you don't need to keep refactoring code like in other languages. The compiler helps you refactor your code. It gives warning when you pass an unwanted parameter to your function.

    There is transparency in data structures. Data structures are like interfaces.

    Some of the disadvantages are:
  • You have very few libraries for usage
  • Its a functional programming language. So if you have worked on Java C, its going to be difficult to understand its importance in a short duration of time.

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