AjaxQ is a jQuery plugin that implements AJAX request queueing mechanism.

Why?

There are several reasons why you may need to queue AJAX requests and run them in a sequential manner:

• Browsers impose a limit on the number of open connections to the server. All requests that do not fit in the limit are going to wait for being run anyway. Internet Explorer does not open more than 2 connections per server at a time by default. Mozilla Firefox, Opera and Safari have a limit of 8 connections per server.
• Sometimes it is essential to avoid flooding the server with plenty of simultaneous AJAX requests.
• Web application needs AJAX requests to run one by one by design, the order is important.

Ajax Queue is a plugin that helps to manage Ajax race conditions. When multiple Ajax requests are made in rapid succession, the results can be returned out of order. This can cause weird behavior in your application. Ajax Queue is a plugin (actually, 2 plugins) that provide a way to manage these requests. This plugin was written by John Resig and is maintained by Mike Hostetler.