Event loop refers to an infinite cycle of actions which is used for processing data based on callbacks and messages.
An event loop watches for I/O and timer state changes. It queues functions while waiting for unavailable resources, then dispatches them when resources are available.
I've just finished reading the Promises/A+ specification and stumbled upon the terms microtask and macrotask: see http://promisesaplus.com/#notes
I've never heard of these terms before, and now I'm curious what the difference could be?
I've already…
I am thinking about it and this is what I came up with:
Let's see this code below:
console.clear();
console.log("a");
setTimeout(function(){console.log("b");},1000);
console.log("c");
setTimeout(function(){console.log("d");},0);
A request comes in,…
Are there internally two event loops in nodejs architecture?
libev/libuv
v8 javascript event loop
On an I/O request does node queue the request to libeio which in turn notifies the availability of data via events using libev and finally those…
I've been getting more into the internals of the Node.js architecture, and a term I see coming up a lot is "tick" as in "next tick of the event loop" or the function nextTick().
What I haven't seen is a solid definition of what exactly a "tick" is.…
If you have worked with gui toolkits, you know that there is a event-loop/main-loop that should be executed after everything is done, and that will keep the application alive and responsive to different events. For example, for Qt, you would do…
I have a small GUI test with a "Start" button and a Progress bar. The desired behavior is:
Click Start
Progressbar oscillates for 5 seconds
Progressbar stops
The observed behavior is the "Start" button freezes for 5 seconds, then a Progressbar is…
let x = 0;
async function test() {
x += await 5;
console.log('x :', x);
}
test();
x += 1;
console.log('x :', x);
The values of x logged are 1 and 5. My question is: why is the value of x 5 on second log?
If the test is executed after x…
I can not understand how the following code run. Why "1" is after "b" but "h" is after "3"? Should'n the order be: a, b, 1, 2, h, 3? Some articles said that the difference between "event loop queue" and "job queue" leads to the following output. But…
I would like to start a blocking function in an Executor using the asyncio call loop.run_in_executor and then cancel it later, but that doesn't seem to be working for me.
Here is the code:
import asyncio
import time
from concurrent.futures import…
I've read this and this, watched this...
I've made a diagram of how I understand it:
Javascript callbacks (functions) can be present in the current queue, check queue, close callbacks queue, timers queue and I/O callbacks queue.
Js code gets…
I am curious about the relationship between Event Loop and Promise.
The demo exposes the question. I expected the p1 fulfilled appear in the middle, since they queue a task to the same task queue and are executed one by one.
var p1 = new…
Is there any way to integrate Boost.Asio with Qt4 (preferred) or GTK main loop?
GTK provides poll(2) like API so technically is should be possible. Qt provides its own networking layer, however I prefer to use existing code written for Boost.Asio.
I…
I am aware JavaScript is single-threaded and technically can’t have race conditions, but it supposedly can have some uncertainty because of async and the event loop. Here’s an oversimplified example:
class TestClass {
// ...
async…
Recently, I've been diving into the Twisted docs. From what I gathered, the basis of Twisted's functionality is the result of it's event loop called the "Reactor". The reactor listens for certain events and dispatches them to registered callback…
