Understanding the node.js event loop

So the largest waste with current programming technologies comes from waiting for I/O to complete. There are several ways in which one can deal with the performance impact (from Sam Rushing): The second basis thesis is that thread-per-connection is memory-expensive: [e.g. that graph everyone showns about Apache sucking up memory compared to Nginx] Apache is multithreaded: it spawns a thread per request (or process, it depends on the conf). You can see how that overhead eats up memory as the number of concurrent connections increases and more threads are needed to serve multiple simulataneous clients. There is no way of making code run in parallel within a single request. If you do that in one request, other requests can be processed just fine while the database is running it's sleep. Having asynchronous I/O is good, because I/O is more expensive than most code and we should be doing something better than just waiting for I/O. First-class functions. E.g. I really enjoyed your article. Ed, ed Related: TUTORIELS, COURS, FORMATIONS ETC

Asynchronous Code Design with Node.js – Shine Solutions Group The asynchronous event-driven I/O of Node.js is currently evaluated by many enterprises as a high-performance alternative to the traditional synchronous I/O of multi-threaded enterprise application server. The asynchronous nature means that enterprise developers have to learn new programming patterns, and unlearn old ones. They have to undergo serious brain rewiring, possibly with the help of electroshocks. Start Rewiring To work with Node.js it is essential to understand how asynchronous programming works. Dependent and Independent Code Callback functions are the basic building block of asynchronous event-driven programming in Node.js. The following shows an example of how to switch a synchronous I/O operation to the asynchronous counterpart, and shows the use of the callback function. Synchronous Asynchronous var fs = require('fs'), processId; fs.readdir(" In the synchronous example the CPU waits at the fs.readdirSync() I/O operation, so this is the operation that needs to be changed.

Books and videos so you can easily learn Node.js programming By: +David Herron; Date: 2017-07-01 11:19 Tags: Have you heard about Node.js, but aren't sure what it is? Maybe you know about this exciting new software development platform, Node.js, but don't know where to start learning it? Node.js is an exciting new platform for developing web applications, application servers, any sort of network server or client, and general purpose programming. By supporting JavaScript on the server it means software teams can share code and ideas and methodologies between front-end and back-end. There is tremendous excitement about Node.js, and it's already widely used in production websites. Node.JS Web Development - Third Edition An excellent introduction to web application development in Node.js. NOTE -- I am the author of this book. Node.js in Action An example-driven tutorial on Node.js software development. Web Development with Node and Express: Leveraging the JavaScript Stack UDEMY: The Complete Node JS Developer Course UDEMY: Advanced Node.js Development

Felix's Node.js Guide workshopper/learnyounode: Learn You The Node.js For Much Win! An intro to Node.js via a set of self-guided workshops. Docs There are several types of documentation available on this website: API reference documentationES6 featuresGuides API reference documentation The API reference documentation provides detailed information about a function or object in Node.js. This documentation describes the built-in modules provided by Node.js. ES6 features The ES6 section describes the three ES6 feature groups, and details which features are enabled by default in Node.js, alongside explanatory links. Guides The Guides section has long-form, in-depth articles about Node.js technical features and capabilities.

NodeJS : Qu'est ce que NodeJS ? NodeJS est une plateforme construite sur le moteur JavaScript V8 de Chrome qui permet de développer des applications en utilisant du JavaScript. Il se distingue des autres plateformes gràce à une approche non bloquante permettant d'effectuer des entrées/sorties (I/O) de manière asynchrone. Pourquoi NodeJS ? Avant de commencer à découvrir une nouvelle technologie, il est important d'en comprendre les spécificités. Pour comprendre nous allons partir de la description donnée sur le site officiel : Node.js® is a JavaScript runtime built on Chrome's V8 JavaScript engine. built on Chrome's V8 JavaScript engine : Afin d'interpréter le code que l'on va écrire en JavaScript NodeJS se repose sur le moteur V8 qui équipe actuellement Chrome. Ce que n'est pas NodeJS NodeJS n'est pas un framework.

Node.js Tutorial Node Hero - Node.js Database Tutorial This is the 5th post of the tutorial series called Node Hero - in these chapters, you can learn how to get started with Node.js and deliver software products using it. In the following Node.js database tutorial, I’ll show you how you can set up a Node.js application with a database, and teach you the basics of using it. Storing data in a global variable Serving static pages for users - as you have learned it in the previous chapter - can be suitable for landing pages, or for personal blogs. Let’s take a simple example: user signup. If a user wants to sign up for your application, you might want to create a route handler to make it possible: This way you can store the users in a global variable, which will reside in memory for the lifetime of your application. Using this method might be problematic for several reasons: RAM is expensive,memory resets each time you restart your application,if you don't clean up, sometimes you'll end up with stack overflow. Storing data in a file NoSQL