Taking advantage of clusters

var cluster = require('cluster');
   
   var numCPUs = require('os').cpus().length;
   
       if (cluster.isMaster) {
         // In real life, you'd probably use more than just 2 workers,
         // and perhaps not put the master and worker in the same file.
         //
         // You can also of course get a bit fancier about logging, and
         // implement whatever custom logic you need to prevent DoS
         // attacks and other bad behavior.
         //
         // See the options in the cluster documentation.
         //
         // The important thing is that the master does very little,
         // increasing our resilience to unexpected errors.
           console.log('your server is working on ' + numCPUs + ' cores');
           
            for (var i = 0; i < numCPUs; i++) {
                   cluster.fork();
                 }
            
         cluster.on('disconnect', function(worker) {
           console.error('disconnect!');
           //clearTimeout(timeout);
           cluster.fork();
         });
   
         
       } else {
           require('./app.js');
       
       }