virtual-worker-pool/worker-test.js

Virtual async workers

// Using timeouts, create a worker pool
var redis = require('redis');
var client = redis.createClient();

var EventEmitter = require('events').EventEmitter;
events = new EventEmitter();

events.on('thread:done', function() {

  var allThreadsDone = true;
  threads.forEach(function(t) {
    if (!t.done) {
      allThreadsDone = false;
    }
  });

  if (allThreadsDone) {
    end = Date.now();

    var diff = end - start;

    console.log('Thread Pool finished at ', diff / 1000, 'seconds');
    client.quit();
  }
});

var vThread = function(id) {
  this.id = id || 'Anon vThread';
  this.tout = null;
  this.count = 0;
  this.totalRecords = 0;
};

vThread.prototype.run = function() {
  var self = this;
  //clearTimeout(self.tout);
  self.count++;
  //console.log(self.id, ' cycle');
  client.get('item', function(err, item) {
    var j = JSON.parse(item);
    if (self.count > 1000) {
      self.totalRecords += self.count;
      console.log('Processed ', self.totalRecords, ' records so far');
      self.count = 0;
      //self.done = true;
      //events.emit('thread:done', {});
      self.cycle();
    } else {
      self.cycle();
    }
  });
};

vThread.prototype.cycle = function() {
  var self = this;
  // self.tout = setTimeout(function() {
  //   self.run();
  // }, 0);
  setImmediate(function() {
    self.run();
  });
};

var threads = [];

threads.push(new vThread('Micheal'));
threads.push(new vThread('JP'));
threads.push(new vThread('Bart'));
threads.push(new vThread('Rachel'));
threads.push(new vThread('Isaac'));

// var start = Date.now();
var end = null;
console.log('starting ', new Date());

threads.forEach(function(t) {
  t.cycle();
});

// var c = 0;
// var b = '';
// var tt = function() {
//   c++;
//   for (var a = 1; a < 1000000; a++) {
//     if (a === 0) {
//       b = a;
//     }
//   }
//   console.log('cycle ', c);
//   setImmediate(tt);
// }
//
// setImmediate(tt);