System Design: Sharded Counters

Problem statement

Real-time applications like Facebook, Twitter, and YouTube have high user traffic. Users interact with the applications and perform multiple operations (view, like, comment, etc.) depending on the application’s structure. For instance, an image is posted on a Facebook page that has millions of followers, and the post likes rapidly increase after each millisecond. Here, counting the likes might be easy for this single image, but what will we do when thousands of such images or videos are uploaded simultaneously by ...