Hi All,
I am working on a screen which has several grids and charts that need to refresh at a fixed interval.
The initial design involves 1 large AJAX request to fetch all the data for the entire screen. But as expected the JSON is very large and too unwieldy to handle. As an alternative we decided to have 5 AJAX requests instead of one that will be fired together to fetch data from the server.
Currently I am working with the test team and developing a proto – a plain web component with Java Servlets that are my “AJAX servlets”. We would be using Apache jMeter for the load test. The problem is jMeter is NOT a browser and I recently learned that some browsers have a limit on the number of simultaneous AJAX requests sent to the server at once. Is this true with major browsers? Can we work this around in some way – like using iFrames instead of AJAX?
Thanks in advance.
Regards,
Yazad Khambata.
Yep. IE limits you to 2
2 simultaneous connections are what you can expect right now
The HTTP 1.1 spec advises clients to only allow 2 simultaneous connections to any originating host. This poses problems for several kinds of real-world workloads in a browser environment and so new browsers (Firefox 3, IE 8, etc.) are implementing higher limits, but the current practical limit is 2 simultaneous connections to any server.
This helps provide a potential answer to your problem, though. You can host your data on another domain and use JSON-P to load a document from another server, although this may have some security implications which you'll need to work through (see the documentation for dojo.io.script for Dojo's support of this method).
Breaking up the workload (as you've outlined) seems like a good strategy to me, and you can use a dojo.DeferredList to manage the asynchronous nature of such as setup in order to be informed when all the "pieces" have arrived.
Regards