While the barista prepares your order, the counter employee is not blocked and can take other customer’s order.The counter employee and barista share all the steps to complete your order.A barista prepares one order at a time.A single counter employee can only help one customer at a time.The coffee shop model of transaction processing is non-blocking: In front of the queue is one counter employee who takes orders and processes payment, and one or more baristas behind the counter are preparing orders. You walk into your local coffee shop, and in front of you is a queue of customers. The teller alone must complete all steps in the transaction before the teller can assist another customer. The nature of a banking transaction is synchronous. To serve more customers or serve customers more quickly, this model can scale in 2 ways: When the entire transaction is complete, you leave the teller window.If the teller cannot handle a step in your transaction, let’s say it requires a supervisor’s approval, the teller is blocked waiting for the approval before he or she may proceed.The teller handles all steps in your transaction in order.A single teller can only help one customer at a time.The banking model of transaction processing is blocking: In front of the queue are several teller windows, and behind each open window sits a teller assisting a single customer. You walk into your local bank branch, and in front of you is a queue of customers. While they serve different purposes, fundamentally, they exist to serve us.
![dw ibm notes dw ibm notes](https://i.ebayimg.com/images/g/UjUAAOSwCGthCUiU/s-l300.jpg)
This story is about 2 familiar types of business: the bank and the coffee shop. You might be wondering, “Why would Node force developers to do this?” I’ll explain the answer to that question in this tutorial and give you a few more Node tools.īut first, I want to tell you a story that illustrates the difference between blocking (synchronous) and non-blocking (asynchronous) coding. If you search the web for Node.js, you won’t have to scroll through many results before a theme becomes apparent: Node.js uses a non-blocking – asynchronous – coding style.
#DW IBM NOTES CODE#
The code you need to follow along with the examples in this learning path is in my GitHub repo. I also cover some key concepts along the way, including Node.js’s module system, performance profiling, and Node’s http module.
![dw ibm notes dw ibm notes](https://image2.slideserve.com/3699947/slide10-l.jpg)
To fully understand this concept, I walk you through 3 different scenarios that compare the 2 programming models and demonstrate why Node’s asynchronous programming model makes it so powerful. In this tutorial, I do a deep dive into asynchronous and synchronous programming.
![dw ibm notes dw ibm notes](https://i.ebayimg.com/images/g/c6YAAOSwIOtg2ghW/s-l300.jpg)
Updated Novem| Published November 14, 2018