Google App Engine Backend Patterns

I’ve been playing with GAE backends since they were made available in 1.5 and have had them running in production for well over a week now. Although the deployment process still has some issue in Java, they have been easy to use and proved very useful to the project I am currently working on. This post was prompted by a comment by OceanDrive on a previous post. Here I want to explore a few uses for backends as well as where I believe you shouldn’t be using them.
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Google App Engine – java.lang.IllegalArgumentException: query not found

If you’ve been developing on Google App Engine for any length of time you will have seen the exception java.lang.IllegalArgumentException : Query Not Found being thrown from time to time. This is likely to become more likely if you move code onto the new backend service as I have recently done. I thought I would spend some time exploring this exception, where it comes from and some strategies for making sure it doesn’t happen in the future.
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Google App Engine Backends Part Deux

A few days ago I wrote up my initial experiences with Google App Engine Backends. I ran into a few problems, as did a few other people. Earlier today I committed to moving from a task queue model and get the backend version up and running for magicaean. I’ve just finished the deployment and everything is running smoothly. So here is an updated description of my experiences.
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Google App Engine Optimisation: Multithreading

Now that my current project on Google App has moved into beta, I’ve started to look at optimising different areas in the application. I’ll be blogging about my experiences here. The first area I decided to look at was to enable multithreaded servlets. I’ll be looking at more obvious optimisations in future posts, but was interested in how Google App Engine would react to this hidden away little tag. But first a brief (and simplified) description of what it is all about.
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