Optimization and performance analysis of JavaScript applications (JS Conf Colombia)

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OPTIMIZATION AND PERFORMANCE ANALYSIS OF JAVASCRIPT APPLICATIONS JÉSSICA FÉLIX (@JESSILYNEH)

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LIFECYCLE OF A JAVASCRIPT APPLICATION @jessilyneh

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Lifecycle of a JavaScript application @jessilyneh Loading the JavaScript application source code

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@jessilyneh

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Lifecycle of a JavaScript application @jessilyneh Loading the JavaScript application source code Analyzing the source code

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@jessilyneh

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@jessilyneh AST (Abstract Syntax Tree)

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Lifecycle of a JavaScript application @jessilyneh Loading the JavaScript application source code Analyzing the source code Compiling the source code into machine code.

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@jessilyneh

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Lifecycle of a JavaScript application @jessilyneh Loading the JavaScript application source code Analyzing the source code Compiling the source code into machine code. Optimizing the code

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Optimizing the code @jessilyneh

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Optimizing the code @jessilyneh

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Optimizing the code inlining @jessilyneh

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Lifecycle of a JavaScript application @jessilyneh Loading the JavaScript application source code Analyzing the source code Compiling the source code into machine code. Optimizing the code Creating the main object and global scope

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@jessilyneh Javascript Engines!

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V8: used in Google Chrome @jessilyneh

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@jessilyneh SpiderMonkey: used in Mozilla Firefox

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@jessilyneh Chakra: Used in Microsoft Edge

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@jessilyneh JavaScriptCore: Used in Apple's Safari

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@jessilyneh Code performance techniques

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@jessilyneh

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@jessilyneh Lazy Loading

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@jessilyneh Deboucing

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@jessilyneh Web Workers

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@jessilyneh Does anyone here use only pure JavaScript in applications?

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@jessilyneh The more libraries, the more complexity, the more performance problems

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@jessilyneh it depends

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@jessilyneh React performance problems

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Use React @jessilyneh React performance problems

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@jessilyneh just kidding!

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Components re-rendering unnecessarily @jessilyneh React performance problems

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Components re-rendering unnecessarily React performance problems @jessilyneh This is not a Javascript problem

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Components re-rendering unnecessarily React performance problems @jessilyneh How can we monitor this problem?

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@jessilyneh react-devtools

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@jessilyneh react-devtools

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@jessilyneh Performance Monitor Developer Tools Google Chrome

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@jessilyneh Monitoring 1 requisition X 1000 requisitions monioring

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@jessilyneh Autocannon Benchmarking tool written in Node.js

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@jessilyneh Climem Monitor the memory consumption of your node process via CLI

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@jessilyneh Clinic.js

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@jessilyneh

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@jessilyneh APM Tools - N|Solid

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@jessilyneh

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Special Tips for web developers @jessilyneh Learn Core Web Vitals Google

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Thank you <3 in/jessilyneh/ @jessilyneh

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References @jessilyneh O'Reilly - High Performance JavaScript https://blog.matheuscastiglioni.com.br/desconstruindo-a-web-como-v8-funciona/ https://efcl.info/2016/03/06/ast-first-step/ https://medium.com/dailyjs/understanding-v8s-bytecode-317d46c94775 https://devporai.com.br/5-dicas-para-otimizar-codigo-javascript/ https://geekflare.com/es/best-javascript-online-compilers/ O'Reilly - David Flanagan - “JavaScript: the Definitive Guide https://www.freecodecamp.org/news/execution-context-how-javascript-works-behind- the-scenes/

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References @jessilyneh https://developer.mozilla.org/pt-BR/docs/Web/JavaScript/Memory_management https://medium.com/@selmankoral/memory-management-in-javascript-781e1098e5b3 https://loadninja.com/articles/debug-javascript-performance/ https://www.wmtips.com/html/lazy-loading-definitive-guide/ https://www.freecodecamp.org/news/javascript-debounce-example/ https://woliveiras.com.br/posts/o-que-e-para-que-serve-throttle%20/ https://developer.mozilla.org/pt-BR/docs/Web/JavaScript/Memory_management https://web.dev/articles/workers-basics?hl=pt-br https://www.freecodecamp.org/news/how-webworkers-work-in-javascript-with-example/

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References @jessilyneh https://github.com/facebook/react/blob/main/packages/react-devtools/CHANGELOG.md https://developer.chrome.com/docs/devtools/performance/reference/ https://github.com/mcollina/autocannon https://www.nearform.com/blog/tracking-memory-allocation-node-js/ https://github.com/mcollina/climem https://clinicjs.org/ https://github.com/clinicjs/node-clinic https://youtu.be/CS03W_YSdJc?si=DrbejVSkuTnUkaR0