1) The document discusses concurrency and the traditional model of sharing data between threads which leads to complexity, bugs, and diminishing returns. 2) It introduces the actor model from 1973 which uses message passing between isolated processes or "actors" to achieve concurrency without shared data. 3) ZeroMQ is presented as a modern implementation of the actor model, allowing applications to connect threads and processes across machines using messaging without locks or shared state.

1. Multithreading Magic Why Everything You Thought You Knew about Concurrency is Bogus, if not actually Totally Insane by Pieter Hintjens, CEO, iMatix FOSDEM 2011

3. m is for mass , the size of the code

4. c is for conflict , when c threads collide

5. The Cost of Concurrency Where we end up Where we start

8. So, locks, semaphores, critical sections

9. So, code that fails by default

10. So, complexity, weird bugs, race conditions

11. Diminishing returns as c exceeds ' a few '

12. A bogus, if not totally insane model

13. The Ideal World Where we end up Where we start

16. Maybe best known via Erlang

20. Cheap and fast networking – check!

25. Process incoming messages from all sources

27. Multiple boxes on one network

29. Free software, LGPL licensed

30. In continuous development since 2007

31. Large, active community (~70 people on IRC)

32. APIs in C, C++, Python, Ruby, Perl, Java, Go, Erland, C#, PHP, Lua, Clisp, Haskell,...

33. Linux, UNIX, OS/X, Windows,...

35. In 2010 we turned ZeroMQ fully over to its community (which we are part of :-)

36. Our business is commercial support for companies using ZeroMQ in infrastructure projects

37. Contact me at [email_address]