Make an Async/Await db call within a Task?

async-await, asynchronous, c#, task-parallel-library, wcf

Solution

First, I suggest you take a step back and really ask if returning early is a good idea. What you're doing is usually dangerous; you're returning the "OK" to the client before doing the actual processing. This is only a good idea if your client knows that "returnValue" doesn't mean the action is complete and only considers it complete upon receiving the "SendReplies".

That said, yes, you should see some benefit from making everything asynchronous that you can. If all your tasks are nonblocking, you'll get better use out of your thread pool (less context switching).

public bool ProcessMessage(string message)
{
  var returnValue = GetReturnValue();

  Task.Run(async () => {
    //do some things with the message
    await UpdateDatabaseAsync();
    await SendRepliesOverNetworkAsync();
  });

  return returnValue;
}

Problem

We have a WCF service that is processing incoming messages in the following manner: ``` public bool ProcessMessage(string message) { var returnValue = GetReturnValue(); Task.Run(() => { //do some things with the message UpdateDatabase(); SendRepliesOverNetwork(); }); return returnValue; } ``` In an effort to process as many messages as possible, we added the task here. We want to return the returnValue to the caller as quickly as possible and let the Task do its thing. My question: is there is any advantage to using the awaitable async database calls and/or using async methods for the replies over the network? I'm cautious, as I think this may create too much context switching. We're already seeing the app using 100+ threads under load.

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