What should you recommend?

You are designing a Windows Azure application. The application includes two web roles and three instances of a worker role. The web roles will send requests to the worker role through one or more Windows Azure Queues. You have the following requirements:

-Ensure that each request is processed exactly one time.

-Minimize the idle time of each worker role instance.

-Maximize the reliability of request processing.

You need to recommend a queue design for sending requests to the worker role.

What should you recommend?
A . Create a queue for each combination of web roles and worker role instances. Send requests to all worker role instances based on the sending web role.
B . Create a single queue. Send all requests on the single queue.
C . Create a queue for each worker role instance. Send requests on each worker queue by using a round robin rotation.
D . Create a queue for each web role. Send requests on all queues at the same time.

View Answer

Answer: B

Explanation:

To communicate with the worker role, a web role instance places messages on to a queue. A worker role instance polls the queue for new messages, retrieves them, and processes them. There are a couple of important things to know about the way the queue service works in Azure. First, you reference a queue by name, and multiple role instances can share a single queue. Second, there is no concept of a typed message; you construct a message from either a string or a byte array. An individual message can be no more than 64 kilobytes (KB) in size.

Explanation:

https://msdn.microsoft.com/en-gb/library/ff803365.aspx

http://azure.microsoft.com/en-gb/documentation/articles/cloud-services-dotnet-multi-tier-app-using-service-bus-queues/