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Apache Spark: map vs mapPartitions?

...ons)? Does it move data between nodes? I've been using mapPartitions to avoid moving data between nodes, but wasn't sure if flapMap would do so. – Nicholas White Jan 18 '14 at 10:52 ...
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Understanding the Event Loop

...run something asynchronously is by invoking one of the async functions provided by the node core library. Even if you are using an npm package that defines it's own API, in order to yield the event loop, eventually that npm package's code will call one of node core's async functions and that's when ...
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C++ Dynamic Shared Library on Linux

...virtual otherwise linker will try to perform static linkage */ virtual void DoSomething(); private: int x; }; #endif myclass.cc #include "myclass.h" #include <iostream> using namespace std; extern "C" MyClass* create_object() { return new MyClass; } extern "C" void destroy_object...
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std::vector performance regression when enabling C++11

...me optimization (I also pass the -flto flag to gcc 4.7.2), the results are identical: (I am compiling your original code, with container.push_back(Item());) $ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out Performance counter stats for './a.out' (10 runs): 35.426...
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Java 8 Streams: multiple filters vs. complex condition

...le filter invocation using a lambda expression with &&. But, as said, this kind of overhead will be eliminated by the HotSpot optimizer and is negligible. In theory, two filters could be easier parallelized than a single filter but that’s only relevant for rather computational intense ta...
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ByteBuffer.allocate() vs. ByteBuffer.allocateDirect()

...at any time. Arrays are objects in Java, and the way data is stored inside that object could vary from one JVM implementation to another. For this reason, the notion of a direct buffer was introduced. Direct buffers are intended for interaction with channels and native I/O routine...
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?

...anteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactly 32-bits. Some have a 9-bit bytes for example, so they don't have a uint32_t. uint_fast32_t states your intent clearly: it's a type of at least 32 bits which is the best from ...
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Why does Unicorn need to be deployed together with Nginx?

...ing Unicorn without a reverse proxy. However, that wouldn't be a very good idea; let's see why. Unicorn follows the Unix philosophy which is to do one thing and do it well, and that is to serve fast, low-latency clients (we'll see what this means later on). The fact that Unicorn is designed for fas...
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How does type Dynamic work and how to use it?

...cs or set the compiler option -language:dynamics because the feature is hidden by default. selectDynamic selectDynamic is the easiest one to implement. The compiler translates a call of foo.bar to foo.selectDynamic("bar"), thus it is required that this method has an argument list expecting a Str...
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Very simple log4j2 XML configuration file using Console and File appender

...) Use Logger logger = LogManager.getLogger(); to initialize your logger I did set the immediateFlush="false" since this is better for SSD lifetime. If you need the log right away in your log-file remove the parameter or set it to true ...