Question

Let’s assume that we have web site which runs on IIS 7.5 and built with ASP.NET MVC 3. Also assume that this website has lots of unique pages for products and all of that pages is being cached for 24 hours in memory. There are other pages also which benefits from output caching.

Everything is fine till here. As soon as we deploy a new update into IIS, the pool is recycled and all of the cache is gone.

So, I consider building a console app which basically do one thing: go and consume every single page for the website.

Is this the way of doing that sort of thing? Is there any known method for that?

Answer 1

There are many ways to address this issue. A few:

1. Pre-cache the data in SQL Server by issuing queries that read the required tables into RAM. Of course, you need enough RAM for the tables to fit. You can run the task from SQL Agent at a specific time.
2. Add a distributed caching middle tier, such as AppFabric (warning: potential headaches)
3. Use .NET 4.0 app auto-start and a cache pre-warming class
4. Use Application_Start() in global.asax
5. Start a background thread in your app that reads in the required data structures
6. Use ASP.NET object caching in addition to output caching, and pre-load the object cache using one of the methods above
7. In addition to or instead of issuing DB queries from your background thread or cache warmer, use the WebRequest class to fetch a copy of each page in your app, which will cause it to be loaded in the output cache
8. Set your AppPool to recycle at a specific time of day, and have a Windows Scheduled Task that runs at a specific time after that, which causes the pages to be loaded, etc.