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If you've ever looked at Firebug when loading a profile page, you're familiar with the flurry of activity involved in loading an OpenSocial app—but this doesn't mean your app can't be snappy to load. This field manual contains tactics for reducing latency in your app that will decrease the load on your servers and provide a better experience for your users.
Be sure to read the Latency Measurement guide to get an accurate measurement of your app's latency.
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It's much faster to request data from the container than it is to hit your own server. There are lots of ways you can cache your application data in the Persistence API and speed up page loads. The profile view is a great place to do this because it gets a lot of page views and there is less dynamic content.
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