WebAssembly in NodeJS

My presentation about WASM in NodeJS @ NodeJS Meetup Berlin

Transcript

1. The Need for Speed and WebAssembly Willian Martins Autumn 2017
3. Timeline…
4. How did we achieve it Moore law Pushed Tech industries to evolve until today Allowed huge computation power even on small devices
5. All this power for what? Faster applications More immersive games Virtual reality Augmented reality Live video/image processing Big Data/Machine learning
6. The languages over time
7. But what about JS?
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
10. JS - 2008 until now 2008 - JIT Compiler by google w/ Chrome Jump of performance Allowed more complex applications What is the next step?
11. Willian Elia @wmsbill
13. WE’RE HIRING!!
14. What is WebAssembly?
15. What’s WebAssembly? New binary format Run compiled programs (C, C++, Rust) on a browser Works alongside Javascript Performance and flexibility API
16. Why WebAssembly is faster?
17. V8 - JiT in action
18. V8 - JiT in action
19. V8 - JiT in action
20. V8 - JiT in action
21. V8 - JiT in action
22. V8 - JiT in action
23. V8 - JiT in action
24. JiT: Code life cycle in summary 1. Parse 2. Compile 3. Optimize (de-optimize) 4. Execute 5. Garbage Collector
25. WebAssembly
26. WebAssembly is fast Parse Compile Optimize Execute GC Decode Compile + Optimize Execute JS WASM
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
28. So WebAssembly looks fast, let’s see how to use it
29. How to run WASM modules Current situation: not possible to run WASM modules on their own Need for some Javascript glue
30. WebAssembly JS API 1. Fetch/Load the module binary 2. Instantiate it 3. Access exported functionalities
31. fs.readFile(‘./module.wasm’, async function(err, file) => { const { instance } = await WebAssembly.instantiate(file); // Do something with the compiled results! });
32. How to generate a WASM file
33. Compile C to WASM + JS WASM emcc my-module.c -o my-module.js -s WASM=1
34. Then we can simply import the generated JS code as a module
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
36. What about WebAssembly memory? How can we access it?
37. Memory management Emscripten provide three useful functions to manage WebAssembly memory _malloc(memoryNeeded) getValue(ptr, type) setValue(ptr, value, type)
38. Elia @eliamain
39. DEMO TIME
40. The WASM implementation was still slower
41. Why??
42. JIT handover
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
44. The future of WebAssembly
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

46. Danke! Thank you!
47. What about Native modules?