Understand the main loop of message-passing-interface software

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In video games, the main loop usually looks like this:


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while(running){
    processInput();
    updateGameState();
    drawScreen();
}


(from higherorderfun.com)

Message-passing-interface (MPI) software can be designed in a similar fashion.

Each message-passing-interface rank of an MPI software has its own message inbox and its own message outbox.

Like for emails, received messages go in the inbox and sent messages go in the outbox.

The main loop of an MPI rank usually looks like this:

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while(running){
    receiveMessages();
    processMessages();
    processData();
    sendMessages();
}

This general architecture is utilised in the Ray de novo genome assembler.

Read the code: github.com/sebhtml/ray

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