Tag: concise

The Case for Concise Posts

Ilya SherLeave a comment

According to DiSC, about a quarter of all people should be communicating like me. We want information, not fluff or stories. We are here to get the answer to our question: “what’s X?” (a technology, a format, a piece of software, etc). Yet, the number of blog posts which answer “What’s X?” concisely is roughly zero. I am going to fix this with my future posts as time allows. Stay tuned.

Everything below is implementation detail. You can stop reading here and save a few minutes.

Here is my plan. Feel free to use it as a guideline for your blog posts too.

Discretion

We are looking for the author’s discretion about what’s important (hint: typically concepts and architecture), not a dump of everything that the author knows about the topic. We are here for “I would have written a shorter letter, but I did not have the time“. Yes, that 5 minutes read should take hours if not days to write. Otherwise, what’s the value?

Can’t answer the question concisely? We doubt your understanding of the topic.

Context

“Context is important, the blog post must provide context, blah blah …”.

The context was already established by searching “what’s X” or following a link to the post. It’s annoying when the text starts with fluff, keeping us wondering when and whether my question will be answered.

If there is some *really* important context, that’s not 5 paragraphs. Sorry, storytellers.

Show why the Topic is Important

“You need to show why X is important and where it’s used”.

This information is available in every other blog post and/or on Wikipedia and/or is one search away.

Underlying Concepts

Don’t explain the underlying concepts, link to them (like DiSC above). Don’t waste our time if we already know that.

Stay tuned.

Event Loop for Beginners

Ilya SherLeave a comment

The aim of the post is to give a simple, concise, and high level description of the event loop. I’m intentionally leaving out many details and being somewhat imprecise.

If you need detailed picture, follow the links in this post. In this case, I recommend reading this short post first.

Why Event Loop?

To deal with concurrency (multiple “things” need to be happening at what looks like the same time), there are few models. To discuss the models, we need to know what a thread is.

Roughly, a thread is a sequence of computing instructions that runs on a single CPU core.

Roughly, Event Loop manages on which tasks the thread works and in which order.

Queue

The queue contains what’s called in different sources messages, events, and tasks.

Message/event/task is a reference to a piece of code that needs to be scheduled to run. Example: “the code responsible for handling the click of button B + full details of the click event to pass to the code”.

Event Loop

  1. The queue is checked for new tasks. If there is none, we wait for one to appear.
  2. The first task in the queue is scheduled and starts running. The code runs till completion. In many languages, await keyword in the code counts as completion and everything after await is scheduled to run later – new task in the queue.
  3. Repeat from number 1. That’s the loop. It’s called Event Loop because it processes events from the queue in a loop.

Adding Events to the Queue

Tasks are added to the queue for two reasons:

  1. Something happened (user clicked on a button, network packet arrived, etc).
  2. The code that was running in step 2 of the event loop scheduled something to run later.

See Also

  1. Event Loop documentation at MDN.
  2. What is the difference between concurrency and parallelism? at StackOverflow

Hope this helps with high level understanding of Event Loop. Have a nice day!