Linux Systems Programming: Multithreading
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      * * **Duration**
	* 2 days
      * * **Language**
	* Trainer language is English or German
      * * **Material**
	* * PDF Slides, :download:`sysprog </trainings/material/pdf/020-linux-sysprog--en.pdf>`
      * * **Related**
	* * :doc:`basics`
	  * :doc:`advanced`
	  * :doc:`network`
	  * :doc:`/trainings/repertoire/linux-prog/linux-basics`
      * * **Booking**
	* :doc:`/trainings/booking`


Parallel programming is hard - this is no different on Linux. This
course gives a solid overview of multithreading on Linux (POSIX
threads, basically), and its mechanisms for synchronization and
communication. Ah, yes, realtime.

.. image:: salad-mt-small.jpg
   :alt: Applied Multithreading
   :align: right

Course Outline
--------------

* **Thread lifecycle**. Once started, threads need to be managed, and
  sometimes they also need to be terminated.

  * Thread creation
  * *Joinable* vs. *detached*
  * Thread termination
  * Thread attributes: realtime properties

* **Raceconditions, and avoidance**. In the face of multithreading,
  all code you write can only be wrong. Why is that?

  * Load-Modify-Store: the mother of all raceconditions
  * Mutexes: types (e.g. normal vs. recursive), usage
  * Atomic operations on builtin types

* **Communication mechanisms**. Understanding *condition variables*

  * Principles: the lost wakeup bug
  * Exercise: a handwritten message queue
  * Exercise: mimicking WIN32 auto reset events

* **Miscellaneous**.

  * One-time initialization
  * Thread Specific Data (Thread Local Storage)

* **Realtime**. Yes, Linux is a realtime OS.

  * Scheduling policies: FIFO, round robin, batch, deadline ...
  * Scheduling priorities
  * Bugs, bugs: priority inversion, and avoidance
  
Prerequisites
-------------

A solid understanding of the C programming language is helpful. Fun
with low-level hacking is required.