How can I read messages from a queue in parallel?

Question

Situation

We have one message queue. We would like to process messages in parallel and limit the number of simultaneously processed messages.

Our trial code

Answer 1

The task library in .NET is made to execute a number of tasks in parallell. While there are ways to limit the number of active tasks, the library itself will limit the number of active tasks according to the computers CPU.

The first question that needs to be answered is why do you need to create another limit? If the limit imposed by the task library is OK, then you can just keep create tasks and rely on the task library to execute it with good performance.

If this is OK, then as soon as you get a message from MSMQ just start a task to process the message, skip the waiting (WhenAll call), start over and wait for the next message.

You can limit the number of concurrent tasks by using a custom task scheduler. More on MSDN: https://msdn.microsoft.com/en-us/library/system.threading.tasks.taskscheduler%28v=vs.110%29.aspx.