I am developing a PaaS. The application will be hosted in Azure websites. Currently I am using EF / SQL as a datastore with in memory caching. I was planning on using the Azure Reddis Cache if the application grows and I need to share this cache across multiple instances.

As I looked more into reddis I started to like what I saw. It was really fast and perfect for a number of my domain objects. My logging model for instance. So now I am wondering, can I use Azure Reddis Cache as a primary data store ?

The word Cache in the name has me concerned. Is the data purged when not being used ?

While Im at it, I guess I should describe my app in a little more detail. The app is a MVC5 app. It includes a HtmlController administration section but the meat of the work is in an ApiController. The ApiController will serve mostly OData Get's, but I will have my share of PUT requests as well. I bill by request, so all user actions must be logged (a perfect job for reddis).

Edit

My model has three objects and no relations. User's which is used infrequently for authentication. Logging which is 90% put 'fire and forget', and Storage which is partitioned by 'app key' and 'group key'. Storage 'sets' will be requested and the Odata verbs will be applied manually in memory.

Edit

After some more reading, Im wondering id Azure Tables would be a better solution. This Blog was influential. Hypothetical replacing both the cache and sql.

Edit : Emailed Azure

So I emailed Azure....

Hello Nicholas, Your question appears to require technical support instead of billing and subscription support as selected. Presently you don’t have a Windows Azure Technical Support subscription. Please note that Windows Azure has many options for you to choose from to receive technical support. Have you tried searching or posting your question in our community forums? The Windows Azure ecosystem provides answers to a large number of technical questions that occur frequently. Additionally, if you go to WindowsAzure.com/support you will see we have several paid support options and you can choose the one that best meets your technical support needs.

Really ? That is NOT how you do pre-sales inquiries.