In this post I’ll walk through replacing existing, expensive synchronous loop code with an easy to consume generic wrapper to run the code in parallel and increase performance.
I had an interesting challenge today. I was debugging a bit of code related to RSS feed item retrieval and aggregation and saw an opportunity to increase performance by multithreading my calls to different feed urls.
The code in question got List<string> urls which were links to various RSS feeds and returned a single SyndicationFeed item containing all the items from these various feeds ordered by the PublicationDate in descending order. The problem was the loop of the urls was being done one at a time and as anyone who has had to work with WebRequest and WebResponse objects knows, this can be a little costly for one request, let alone many. I knew I needed to get these requests going in parallel to cut down on all the overhead and wait time.