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Introducing Nexus.js: A multi-threaded JavaScript run-time

Abdullah Ali on December 09, 2017

First of all, I recommend reading the old series if you're not familiar with this project. If you don't want to read all of that, no worries! I got...

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spyke • Dec 18 '17

let count = 0;

acceptor.on('connection', (socket, endpoint) => {
  const connId = count++;

How does it work? If event listeners run on parallel threads, there will be a race condition in the increment without synchronization.

Abdullah Ali • Dec 18 '17

Hi! Concurrent access to variables does not corrupt them or cause a race condition. All variables behave atomically in Nexus.

Read more here: nexusjs.com/architecture/

spyke • Dec 18 '17 • Edited

So, in this particular example

When two different execution contexts that share a closure variable are entered in parallel, one will acquire a lock

means that a listener will lock on parent closure right at the start of the function till its end? Or it will lock only from the time of identifier resolution for count to finishing its value reading?

Abdullah Ali • Dec 18 '17

It will only lock upon access to the variable and then it will release the lock as soon as it is done.

spyke • Dec 19 '17

Thank you.

Abdullah Ali • Dec 19 '17

You’re welcome :)

Brandon Ros • Dec 18 '17

Post a graph comparing a similar node.js application (and maybe even Java/Haskell/whatever people compare these days) and show how this handles concurrent requests in a more performant fashion?

Abdullah Ali • Dec 18 '17

That’s all planned. :)

I’m just waiting till Nexus is a little more mature before making big comparisons.

Joe Pea • May 22 '19

A simple test comparing simple things like many setTimeout operations compared to Node.js would be nice, before the more complicated tests.

Sreejith • Dec 15 '17 • Edited

Few newbie questions.
Where can I use this? inside a node server? or can I use it on the clientside?
From the docs it says multi-threaded JavaScript run-time, so is it like V8?
Can we make use of WebAssembly and create a library to support multi-threading much more effectively?

Abdullah Ali • Dec 15 '17

Hi! You can only use Nexus on the server right now. It's a stand-alone environment and doesn't require a Node.js installation.

It's not based on V8, it's based on JSC.

I just introduced WebAssembly support to the repo. So yes, you can use multi-threading with WebAssembly now. Although I'm still ironing out the details.