ASP.NET MVC and long running actions

Question

I have a controller action that aggregates data from multiple sources: web service, database, file lookups, etc... and passes results to the view. So in order to render the page all tasks must have completed. Currently they are performed sequentially but as they are independent I am thinking of running them in parallel as this could improve performance.

So what would be the best approach to achieve this? For each task start a new thread and block the main thread as all tasks are finished? Should I use a thread from the thread pool or spawn a new thread manually? Using threads from the thread pool would limit my web server's capability of serving new requests so this might not be a good idea. Spawning new threads manually could be expensive, so at the end of the day would there be a net gain in performance by paralleling these tasks or just leave them run sequentially?

Answer 1

The only way to answer your final question would be to actually test it out, as we don't know how complicated the separate aggregation tasks are. If you want to give the illusion of a responsive UI, you could always display the loading page and kick off the aggregation with AJAX. Even non-threaded, this may placate your users sufficiently.

Answer 2

If it's between spawning your own threads or using the thread pool threads, I'd say use the ones from the thread pool. You can always adjust your server settings to allow for more threads in the pool if you find that you are running out of threads.