var http=require('http'),
   cluster=require('cluster'),
   cpus=require('os').cpus().length;
 if (cluster.isMaster) {
  for(var i = 0; i < cpus; i++) {
   cluster.fork();
  }
 } else {
  http.createServer(function(req, resp) {
   resp.writeHead(200, {'Content-Type': 'text/plain'});
   resp.end(req.url);
  }).listen(3000);
 }