How many Azure instances to support 1000 connections

If I have a WCF service hosted in an Azure webrole, how many small machine instances would I need to spin up so that potentially 1000 clients could be connected at once?

Processing power is not the issue I'm concerned about, just the maximum number of active connections that Azure will allow me to have open at any given moment.

We have a service method that will take some time to 开发者_开发技巧complete (say 20-30 seconds) and we need to know roughly how many open connections Azure will allow us to have per small instance so we can ensure 1000 people man connect at once.

Thanks!

The limit @Jordan refers to is the number of IIS threads that can be active. Following @Jordan's link to here you will see that the IIS threads will get passed off to .Net threads while .Net is handling them.

Your .Net threads are effectively limited by the resources on the system, although 1000 might be OK. Better would be to pass the requests off to asynchronous handlers (if you can - I don't know what you are trying to do), which leaves only the maximum number of open TCP connections Windows Server 2008 R2 will allow, which should not be a problem for 1000 connections.

Existing answers mostly cover it, but a different type of answer is that Windows Azure doesn't care how many connections you have. Your question then becomes one about Windows and IIS/.NET/WCF or whatever technology you choose to use.

Looks like for .NET 3.5 it was 12, and in .NET 4.0 it's 5,000. Not sure how they decided on those numbers.

source: http://social.msdn.microsoft.com/Forums/en-US/windowsazure/thread/a6a4213b-b402-4a6c-940c-10937e34d9b5/

There is no limit with Azure Webrole - the only limits are whatever you've purchased - things like CPU, RAM, bandwith.