Why aren't my JQuery .ajax requests being made in parallel?

I am trying to make two ajax requests in parallel using jQuery like this:

    var sources = ["source1", "source2"];

    $(sources).each(function() {
      var source = this;
      $.ajax({
        async: true,
        type: "POST",
        data: {post: "data", in: "here"},
        url: "/my/url/" + source,
        success: function(data) {
          process_result(data);
        }
      });
    });

I got the basic structure from this question, but my requests still aren't being made in parallel. "source1" takes a while to complete, and I can see on the server that the second request isn't made until the first is completed.

As far as I can tell, I don't have any other acti开发者_如何学Pythonve requests, so I don't think it's a problem with the maximum number of parallel requests for the browser. Am I missing something else here?

jQuery does not queue AJAX requests. If you're sure you're not making any other requests your end, how about the server? Maybe it only has one worker?

EDIT: And just to make sure, I tested it with a script that launches 2 AJAX POST requests to a PHP script which sleeps for 5 seconds. They were not queued.

are you using php? are you using session_start()? sessions cannot be opened in parallel by multiple requests, to they will wait one after another to finish what they're doing.

What if you used $.post instead of $.ajax. This works for me.

var sources = ["source1", "source2"];

$(sources).each(function() {
  var source = this;
  $.post("/my/url/" + source, {post:"data", in:"here"}, function(data) {
      process_result(data);
  });
)};