NodeJS-HTTP请求的并行执行

Question

I need to simulate a user scenario of parallel and sequential executions of http request (invoke a web service and measure time to deliver the response)

                function 1
 function2  |   function3      | function4

So function1 execute first as soon as it's done I need to perform parallel execution of functions 2, 3 and 4
How do I control the execution of function 2,3 and 5 and force parallel execution? is this possible with nodejs? does async.parallel provide this result? is there any valid multi-threading in NodeJS to allow real parallel execution?

Answer 1

Create async functions:

var function2 = function(callback){
    process.nextTick(function(){
        callback();
    });
};
var function3 = function(callback){
    process.nextTick(function(){
        callback();
    });
};
var function4 = function(callback){
        process.nextTick(function(){
            callback();
        });
    };

Call:

function1(); //sync
function2(function(){}); //async
function3(function(){}); //async
function4(function(){}); //async