There are plenty of related posts plugins available for WordPress sites. Not all of them have an optimized code. In fact, many of these plugins put too much load on your server, slow down your site, and even completely crash it. The Related Posts module for Jetpack is different. It lets you display related posts above or below your posts without having to worry about breaking your server.
What’s neat about this module is that you can customize it easily. We have already covered how you can change the title and look of your related posts box. To change the number of related posts displayed above or below your posts, you will need to use jetpack_relatedposts_filter_options. On our own websites, we have not gone above 4 related posts per page, but some webmasters have used larger numbers to display as many similar posts as possible.
The Related Posts module may not slow down your site like a few other top related posts plugin, but you still should be careful how you integrate it into your site. The above code simply lets you change the number of posts shown above or below your posts.