congestion-control

Control the number of concurrent running tasks. When a task fails (return a rejected promise) the module retry to run it a configured number of times.

Inspired by TCP congestion control mechanism. The mechanism has a window of size n, which contains the current running tasks, and a queue which contains all the rest of the tasks. The window size increase or decrease itself by watching the number of success or fail responses.

Usage

const {Congestion} = require('congestion-control');
const addTask = Congestion();
const aTask = () => {
    return Promise.resolve('aTask is finished');
};

addTask(aTask).then( result => {
    console.log(result);  //aTask is finished
});

Configurations

retries (default 3)

When the task fails by returning a rejected promise the module will retry to tun it retries times.

const {Congestion} = require('congestion-control');
const addTask = Congestion({
    retries: 3
});

initialWindowSize (default 1)

The initial number of tasks the module will run concurrently. All the rest of the tasks will wait on a queue till one of the running tasks finishes. The window size will adjust itself automatically to the optimal size.

const {Congestion} = require('congestion-control');
const addTask = Congestion({
    initialWindowSize: 10
});

maximumWindowSize (default Infinity)

Maximum number of tasks the module will run concurrently. Note that if initialWindowSize is bigger than maximumWindowSize then initialWindowSize will be equal to maximumWindowSize

const {Congestion} = require('congestion-control');
const addTask = Congestion({
    maximumWindowSize: 9
});