42 lines
1.4 KiB
JavaScript
42 lines
1.4 KiB
JavaScript
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const cluster = require('cluster');
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let workers = [];
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/**
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* @module A module for creating and managing multiple workflows (worker) in Node.js.
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*/
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module.exports = () => {
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// to read number of cores on system
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let numCores = require('os').cpus().length;
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console.log('Master cluster setting up ' + numCores + ' workers');
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// iterate on number of cores need to be utilized by an application
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// current example will utilize all of them
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for(let i = 0; i < numCores; i++) {
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// creating workers and pushing reference in an array
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// these references can be used to receive messages from workers
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workers.push(cluster.fork());
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// to receive messages from worker process
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workers[i].on('message', function(message) {
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console.log(message);
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});
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}
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// process is clustered on a core and process id is assigned
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cluster.on('online', function(worker) {
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console.log('Worker ' + worker.process.pid + ' is listening');
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});
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// if any of the worker process dies then start a new one by simply forking another one
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cluster.on('exit', function(worker, code, signal) {
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console.log('Worker ' + worker.process.pid + ' died with code: ' + code + ', and signal: ' + signal);
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console.log('Starting a new worker');
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cluster.fork();
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workers.push(cluster.fork());
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// to receive messages from worker process
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workers[workers.length-1].on('message', function(message) {
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console.log(message);
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});
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});
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};
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