Frontend Track NodeJS
0 likes73 views
The document discusses NodeJS, an asynchronous and event-driven JavaScript runtime. It describes how NodeJS works with a single-threaded event loop model to handle requests efficiently via non-blocking I/O. Key aspects covered include the V8 engine, event loop phases, streams, clusters, workers, and common uses of NodeJS like real-time web applications and APIs.
Frontend Track NodeJS
- 2. About me ❏ Software Architect at ilegra ❏ AWS & GCP ❏ Google Cloud Architect Certified ❏ Microservices / DevOPS ❏ Mortal Kombat Player :D ❏ https://github.com/marceloserpa/ ❏ https://www.linkedin.com/in/marceloserpa/
- 3. How works the traditional way ❏ thread per request model ❏ One thread for the entire request flow
- 4. How works the traditional way ❏ Waste resources with waiting threads ❏ Threads are expensive ❏ Limitations 1 thread == 1MB (around it) ❏ Operational System needs to handle threads ❏ You need more hardware
- 5. Blocking and synchronous ❏ Sequential ❏ Unnecessary waiting time ❏ Total time is high
- 6. Restaurant … bad restaurant Imagine: ❏ 1 chef per client ❏ The chef take an order ❏ The chef the cook the plate ❏ The chef accept payment ❏ Go to the next client ❏ … Is it make sense?
- 7. Restaurant … good restaurant Imagine: ❏ 1 waiter and 1 cooker ❏ The waiter ❏ take the orders from many clients ❏ send orders to Cooker ❏ bring the plate to client from kitchen ❏ accept payment ❏ The Chef ❏ Cook the plates
- 8. Whats is NodeJS ❏ Platform built on top Chrome v8 engine ❏ Asynchronous event-driven ❏ Non-Blocking I/O ❏ Focused on network application ❏ Created by Ryan Dahl ❏ 05/27/2009 ❏ Inspired by ❏ NGINX architecture ❏ Twisted ❏ Event Machine ❏ Reactor Pattern
- 10. Single Thread model ❏ One thread to handle requests ❏ Delegate I/O to Thread pool ❏ 0 thread waiting
- 11. NonBlocking and Asynchronous ❏ Initialize something now ❏ Using Threads Efficiently ❏ Scalability ❏ More efficient (doing more with less resources) ❏ Concurrency
- 16. Architecture
- 17. v8 ❏ Engine open-source de JavaScript ❏ Created by Chrome Team ❏ Written in C++ ❏ Implements ECMAScript and WebAssembly ❏ Compile JS to native machine code (JIT) ❏ Handle call stack
- 18. v8
- 19. Core modules - IO Libs ❏ Multithreading ❏ Starts Thread Pool with 4 threads ❏ Default libraries have version blocking for IO methods ❏ Built on top Libuv (Libeio e Libev) ❏ Each O.S have implementation of Event Demultiplexer: ❏ epoll - Linux ❏ kqueue - MacOSX ❏ events ports - Solaris ❏ I/O Completion Port API (IOCP) - Windows
- 20. Event Loop - internals “The event loop is what allows Node.js to perform non-blocking I/O operations — despite the fact that JavaScript is single-threaded — by offloading operations to the system kernel whenever possible.” source: https://nodejs.org/uk/docs/guides/event-loop-timers-and-nexttick/
- 21. Event Loop - internals ❏ 6 phases ❏ Each phase has FIFO queue of callbacks ❏ Event loop move to next phase when all queue has processed ❏ The poll phase are queued by the kernel
- 22. Event Loop - internals ❏ timers: executes callbacks scheduled by setTimeout() and setInterval(). ❏ pending callbacks: executes I/O callbacks deferred to the next loop iteration. ❏ idle, prepare: only used internally. ❏ poll: retrieve new I/O events; execute I/O related callbacks (almost all with the exception of close callbacks, the ones scheduled by timers, and setImmediate()); node will block here when appropriate. ❏ check: setImmediate() callbacks are invoked here. ❏ close callbacks: some close callbacks, e.g. socket.on('close', ...).
- 23. Commons JS ❏ module specification ❏ used is a standard in NodeJS ❏ each file is a module ❏ loaded synchronously ❏ processed in order
- 24. Stream ❏ Streams are implements from EventEmitter ❏ Read chunks from data ❏ Perform specific tasks continuously ❏ Have support to create pipeline ❏ Two main advantages are: ❏ Reduce consuming of memory ❏ Time to processing large files
- 25. Stream sample
- 26. Stream sample
- 29. Cluster mode ❏ Maximize the CPU usage ❏ Fork node process ❏ Load balancing
- 30. Cluster mode
- 31. Cluster mode
- 32. Worker threads ❏ Enable us to create threads ❏ Useful for performing CPU-intensive ❏ Support: NodeJs 10.5 ❏ Never use it for I/O Bound
- 33. Worker threads - define worker thread
- 34. Worker threads - invoking worker thread
- 35. Worker threads - results
- 36. NPM ❏ Node Package Manager ❏ Online repository ❏ Command-line utility ❏ Dependency Manager ❏ Install packages ❏ Basic commands ❏ npm init ❏ npm install <package> --save ❏ npm install <package> -g
- 37. NPM
- 38. NPM
- 39. Companies using NodeJS ❏ Paypal ❏ Ebay ❏ Sony Yahoo ❏ Amazon ❏ Netflix ❏ The New York Times ❏ Salesforce ❏ Linkedin ❏ Uber
- 40. Technologies based EventLoop architecture
- 41. When use ... ● Intensive I/O ● Low CPU processing ● NoSQL ❏ Intensive CPU** ❏ Relational Database When avoid ...