Nodejs中解决cluster模块的多进程如何共享数据问题

var cluster = require('cluster'); 
var data = 0;//这里定义数据不会被所有进程共享，各个进程有各自的内存区域 
if (cluster.isMaster) { //主进程 
 var numCPUs = require('os').cpus().length; 
 for (var i = 0; i < numCPUs; i++) { 
  var worker = cluster.fork(); 
 } 
 data++; 
 console.log('DATA VALUE in MainProcess: %d ' , data);
} else { //子进程,会被调用numCPUs次 
 data++; 
 console.log('DATA VALUE in ChildProcess %d: %d ' cluster.worker.id, data);
}

var cluster = require('cluster'); 
var http = require('http'); 
 
if (cluster.isMaster) { 
 var numCPUs = require('os').cpus().length; 
 var data = 0; 
 // 启动多个进程. 
 for (var i = 0; i < numCPUs; i++) { 
 //增加一个进程 
 var worker_process = cluster.fork(); 
 //侦听子进程的message事件 
 worker_process.on('message', function(msg) { 
  if (msg.cmd && msg.cmd == 'notifyRequest') { 
  data++; 
  console.log('DATA VALUE : %d ', data);
  } 
 }); 
 } 
} else { 
 process.send({ cmd: 'notifyRequest' }); 
}