MetaCall NodeJS C io_uring Example

io_uring is a new Linux Kernel interface that speeds up I/O operations in comparison to previous implementations like libuv (the library that NodeJS uses internally for handling I/O).

This interface is offered through liburing, which provides a C API for accessing it. We could write a NodeJS extension by using N-API, or use ffi in order to call to the library.

Developing those wrappers is costly because either we have to write C/C++ or JavaScript boilerplate. So instead of doing that, we will be using MetaCall in order to achieve this.

MetaCall allows to transparently call to C functions, we can implement anything in C and without need to compile it manually (it will be JITed at load time). So basically we can load C code directly into NodeJS. For example:

int sum(int a, int b) {
	return a + b;
}

const { sum } = require("./sum.c");

sum(3, 4) // 7

With this we can use our C library not only from NodeJS but from any other language, for example, Python:

from sum.c import sum

sum(3, 4) # 7

We will be avoiding all the boilerplate and we will have a single interface for all languages. The calls will be also type safe and we will avoid a lot of errors and time for maintaining the wrappers for each language that we can spend focusing on the development.

In this example we want to bring the power of io_uring to NodeJS for maximizing the speed of I/O and outperform NodeJS native primitives like http module. For demonstrating it, we have a server_listen function which creates a simple HTTP server in the port 8000.

Docker

Building and running with Docker:

docker build -t metacall/nodejs-c-liburing-example .
docker run --rm -p 8000:8000 -it metacall/nodejs-c-liburing-example

Accessing to the website

Just go to your web browser and enter this url: localhost:8000