mongodb的坑

gistfile1.js

//Query, Insert, Update are worked, but CPU load very high in ReplSet mode!
//Explore the cause of the problem
//ACL would blocked all unauthorized network access.
//I found out the problem, it eat the CPU by /lib/mongodb/connection/connection_pool.js.

connection.on("connect", function(err, connection) {
  // Add connection to list of open connections
  _self.openConnections.push(connection);
  // If the number of open connections is equal to the poolSize
  if(_self.openConnections.length === _self.poolSize && _self._poolState !== 'disconnected') {
    // Set connected
    _self._poolState = 'connected';
    // Emit pool ready
    _self.emit("poolReady");
  } else if(_self.openConnections.length < _self.poolSize) {
    // need to open another connection, make sure it's in the next
    // tick so we don't get a cascade of errors
    process.nextTick(function() {
      _connect(_self);
    });
  }
});

//when openConnections.length < poolSize, pool will create a new connection in nextTick.
//But in meantime, if the openning connection emit('close'), this openConnections.length will be cleanup to 0.
//connection.on("close", function() {
  // If we are already disconnected ignore the event
  if(_self._poolState !== 'disconnected' && _self.listeners("close").length > 0) {
    _self.emit("close");
  }
  // Set disconnected
  _self._poolState = 'disconnected';
  // Stop
  _self.stop();
});
//This case will be Infinite loop, open, close, open, close...

//How to fixed this?
//Waiting for your pull request on node-mongodb-native