Question

I have a problem, when i startup my hybrid app. It takes very long to load the first page. ~40 seconds.

I work with GWT, Google App Engine and RequestFactories. I detected, that the app makes several request to the server (~ 10 requests).

Now i wonder, how can i increase the performance of staring up my app.

1. Group all request into one Request, which delivers all data with a single Request.
   (~300kb data)
2. Make a startup page, with low amount of requests and data.
   (~50kb data)
3. Better idea?

I prefer, that i can keep the current startup page. Can you share your experiance?

Answer 1

You have pointed out the two main ways to reduce the start-up time.

1.- Reduce requests: With RF you can group all requests in one if you share the same service instance and call only once the .fire() method. Use Bundles for images, css, and other resources so as them are downloaded in the same request.

2.- Reduce the js size: split your code in pieces using GWT.runAsync(). So the first piece of code could be the minimum stuff for starting your app until the user interacts with it. You can use the gwt compilation reports to see whether your code is bigger. You can use the new closure compiler in gwt-2.5 to reduce and optimize the final js.

3.- Another thing you must check is that your webserver configuration is sending the appropriate headers so as the browser caches gwt fragments, as well as you should check if it is compressing the files before sending to the client. You can make gwt compiler to pre-compress those js fragments though.

4.- For successive loads, I mean the user goes to your app a second time, consider using localstorage for caching certain things which don’t change instead of requesting them again. Configure your HTML5Manifest, if you are using mgwt, it is really easy since they include a linker to produce the manifest in compile time.

5.- Consider using light-weight widgets and frameworks instead of heavy widgets (js collections, elemental, gquery, mgwt, etc).