Multiple roles on the same instance in Windows Azure

Question

Is it possible to deploy multiple roles in the same instance?

I have three web roles (website in asp.net mvc3, and two WCF services instances) and two worker roles (

Answer 1

No, roles are instances and each one takes up an entire VM. You can however deploy a number of websites into a single role, which will allow you to deploy all your MVC and WCF apps into a single web role. You need to add websites to the sites element in the ServiceDefinition. There seem to be a few blog posts on how this is done - here and here.

For worker roles, I suggest you create a single worker role and combine the work done in those roles, such as starting a separate thread for each queue being monitored. This StackOverflow answer by Eugenio Pace.

I wouldn't recommend trying to combine worker role functionality into the web role. Apart from it not making architectural sense, sense to the physical infrastructure (IIS vs not IIS), there are potential issues such as the with termination of running threads when worker roles recycle (a thread not started by IIS may terminate abruptly)