old_contents: "use strict";
  
  var LmdbQueue = require('../'),
      Producer = LmdbQueue.Producer;
  
  var producer = new Producer({ path: __dirname + '/test-data', topic: 'test', dataType: LmdbQueue.STRING_TYPE, chunkSize: 1024 * 1024 * 1024, keepHours: 24 * 2 }),
      start = Date.now();
  
  console.log('Begin write to queue.');
  
  var step = 1024;
  for (var i = 0; i < 10 * 1024 * 1024; i += step) {
      //producer.push('msg' + i);
      var msg = [];
      for (var j = 0; j < step; j++) msg.push('msg' + (i + j));
      producer.push(msg);
  }
  
  console.log('Pushed 1M messages in %d ms', Date.now() - start);
new_contents: "use strict";
  
  var LmdbQueue = require('../'),
      Producer = LmdbQueue.Producer;
  
  var producer = new Producer({ path: __dirname + '/test-data', topic: 'test', dataType: LmdbQueue.STRING_TYPE, chunkSize: 64 * 1024 * 1024, chunksToKeep: 8 }),
      start = Date.now();
  
  console.log('Begin write to queue.');
  
  var step = 1024;
  for (var i = 0; i < 10 * 1024 * 1024; i += step) {
      //producer.push('msg' + i);
      var msg = [];
      for (var j = 0; j < step; j++) msg.push('msg' + (i + j));
      producer.push(msg);
  }
  
  console.log('Pushed 10M messages in %d ms', Date.now() - start);
subject: update example.