Question

I am trying to setup in Windows Azure a global counter which would keep track of the number of games started within a day. Each time a player starts a game, a Web Service call is made from the client to the server and a global counter would be incremented by one. This should be fairly simple to do with a database… But I wonder how I could efficiently do this. The database approach is good for a few hundreds clients simultaneously, but what will happen if I have 100,000 clients?

Thanks for your help/ideas!

Answer 1

A little over a year ago, this was a topic in a Cloud Cover episode: Cloud Cover Episode 43 – Scalable Counters with Windows Azure. They discussed how to create an Apaythy Button (similar to the Like Button on Facebook).

Steve Marx also discusses this in detail in a blog post with source code: Architecting Scalable Counters with Windows Azure. In this solution they’re doing the following:

• On each instance, keep track of a local counter
• Use Interlock.Increment to modify the local counter
• If the counter changed, save the new value in table storage (have a timer do this every few seconds). For each deployment/instance, you’ll have 1 record in the counters table.
• To display the total count, take the sum of all records in the counters table.