WebAssembly in NodeJS

My presentation about WASM in NodeJS @ NodeJS Meetup Berlin

Transcript

1. The Need for Speed
   and WebAssembly
   Willian Martins
   Autumn 2017
   

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3. Timeline…
   

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4. How did we achieve it
   Moore law
   Pushed Tech industries to evolve until
   today
   Allowed huge computation power
   even on small devices
   

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5. All this power for what?
   Faster applications
   More immersive games
   Virtual reality
   Augmented reality
   Live video/image processing
   Big Data/Machine learning
   

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6. The languages over time
   

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7. But what about JS?
   

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8. JS - Early days
   Created in 1995 by Brendan Eich
   Was written in 11 days
   Designed to be easy and simple
   Designed to be a glue code for
   dynamic Web
   

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10. JS - 2008 until now
    2008 - JIT Compiler by google w/
    Chrome
    Jump of performance
    Allowed more complex applications
    What is the next step?
    

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11. Willian Elia
    @wmsbill
    

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13. WE’RE HIRING!!
    

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14. What is WebAssembly?
    

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15. What’s WebAssembly?
    New binary format
    Run compiled programs (C, C++, Rust) on
    a browser
    Works alongside Javascript
    Performance and flexibility
    API
    

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16. Why WebAssembly is
    faster?
    
    

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17. V8 - JiT in action
    

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18. V8 - JiT in action
    

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19. V8 - JiT in action
    

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20. V8 - JiT in action
    

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21. V8 - JiT in action
    

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22. V8 - JiT in action
    

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23. V8 - JiT in action
    

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24. JiT: Code life cycle in summary
    1. Parse
    2. Compile
    3. Optimize (de-optimize)
    4. Execute
    5. Garbage Collector
    

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25. WebAssembly
    

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26. WebAssembly is fast
    Parse Compile Optimize Execute GC
    Decode
    Compile
    +
    Optimize
    Execute
    JS
    WASM
    

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27. WebAssembly is fast
    WASM is more compact -> Faster FETCH of the source
    WASM is closer to machine code -> Faster DECODING,
    COMPILING and OPTIMISING
    No need to RE-OPTIMISE
    No garbage collection
    

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28. So WebAssembly
    looks fast, let’s see
    how to use it
    

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29. How to run WASM
    modules
    Current situation: not possible to run
    WASM modules on their own
    Need for some Javascript glue
    

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30. WebAssembly JS API
    1. Fetch/Load the module binary
    2. Instantiate it
    3. Access exported functionalities
    

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31. fs.readFile(‘./module.wasm’, async function(err, file) => {
    const { instance } = await WebAssembly.instantiate(file);
    // Do something with the compiled results!
    });
    

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32. How to generate a
    WASM file
    

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33. Compile C to WASM
    +
    JS WASM
    emcc my-module.c -o my-module.js -s WASM=1
    

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34. Then we can simply
    import the generated
    JS code as a module
    

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35. Export functions to JS
    Keyword EMSCRIPTEN_KEEPALIVE
    EMSCRIPTEN_KEEPALIVE
    int sum(int x, int y) {
    return x + y;
    }
    Expose only the interface of the WASM module to JS
    

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36. What about
    WebAssembly memory?
    How can we access it?
    

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37. Memory management
    Emscripten provide three useful
    functions to manage WebAssembly
    memory
    _malloc(memoryNeeded)
    getValue(ptr, type)
    setValue(ptr, value, type)
    

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38. Elia
    @eliamain
    

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39. DEMO TIME
    
    

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40. The WASM
    implementation was
    still slower
    

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41. Why??
    

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42. JIT handover
    

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43. “Currently, calling a WebAssembly function
    in JS code is slower than it needs to be.
    The JIT doesn’t know how to deal directly
    with WebAssembly, so it has to route the
    WebAssembly to something that does.
    …
    This can be up to 100x slower than it
    would be if the JIT knew how to handle it
    directly.
    ”
    Lin Clark
    

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44. The future of
    WebAssembly
    

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45. Future features
    Formal Specification

    Threads supports

    SIMD acronym to Single Instruction Multiple Data (back to Stage 3 on TC39) 

    Exception handling

    Garbage collection

    Direct DOM access

    ES6 Module integration

    

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46. Danke!
    Thank you!
    

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47. What about Native
    modules?
    
    

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