Resources to learn and understand parallel programming. The hard way

There’s no way other than the hard way. (c)

Parallel programming is considered as not easy or even advanced topic by many programmers. It’s the starting point for even more advanced stuff like distributed computations, reliability, CAP theorem, consensus problems and much more. Besides, deep understanding of how CPU and operating system works can help you to write less buggy software and parallel programming can help you with that too.

In this post I will focus on books describing parallel programming using 1 computer and 1 CPU using classical approaches. Neither they contain SSE instructions guides nor you will find matterials on CUDA or OpenCL. Similary you will find no resourced about Hadoop and/or MapReduce technologies and nothing about technologies supporting parallel programming out of the box like Go or Erlang.

So I will go now through all the resources which I find more or less useful. I’m not going to stick to any technology in general – the point is to understand the topic from different perspectives. The materials I’m refering to in general should not be considered as entry-level –  they require fair amount of knowledge, but nevertheless, list goes sorted starting from “easier” things.

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.NET String Dictionary vs string switch performance

I had a simple task to map a collection of objects with string property. Map function should replace one string property to another from set of 5-6 strings. Existing solution used Dictionary initialized with those hard-coded values. Once upon a time I tried to compare Dictionary with int keys to int switch and int switch was FAR better. It was chess engine so performance mattered.

Now it’s a web request with thousands of rows of reply, serialized to json, so performance matters again. I wrote simple program, which generated 10 million instances of my simple class with several properties and mapped this list with both methods. Before that I ensured that both methods were JIT’ed. You can find source code at Github.

Details below..

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Solve problem from string

I with my friends joked that someday .NET framework would be so powerful, that it would be possible to write applications using magic method SolveProblemFromString(string problemDescription) like this:

public static void Main()
{
    SolveProblemFromString("I need a new sync app for my iPod player!");
}

So the programmers would be deprecated.