Nodejs + mongodb connection at application start or many when needed, dilemma how to be?

Question

MongoDB

Good afternoon, I have logging in my mongo, on average there are 300-1000 calls per minute, each time I create a connection, write down the log and cut myself off.
Should I use one connection at program start?
When I used mysql, there were pool in the mongo pool of connections, as there are no connections in the mysql library.
here's the dilemma...

Answer 1

Standard mongodb is all included out of the box.
I took the connection to the start of the program, what we have: we increased the upload speed, the load on the hdd decreased by 15%. (total load was 22-23% )

async.parallel([
    function(callback){
        console.log('mongodb callback run');
        var mongodb_url = 'mongodb://localhost:27017/database';
        var options = { server: { auto_reconnect:true, poolSize: 20, socketOptions: { connectTimeoutMS: 2000 } } };
        MongoClient.connect(mongodb_url, options ,function(err, db) {
            assert.equal(null, err);
            mongodb = db;
            callback(null,{event:'init_mongo', reason: 'mongodb connection success'});
        });
    },
  // ....
],function(err,result){
     app.run()  //sertver listen
});

It is beneficial if you constantly receive calls 24/7

Answer 2

The logic of working with MongoDB in the server on Node.JS
(Also, consider using Mongo via mongoose.js, it is even more convenient.)