Imagine a high traffic website that needs post views as an algorithm to display posts on the homepage.
This website also uses Varnish Caching. So we need an AJAX based post views counter.
Now imagine a minimum 5000 concurrent users browsing the website, so we can’t use the default “AJAX in Plugins” as live updates on the backend using update_post_meta will be very painful for the backend.

So what can we do ?

What if all these post views counts will be done in memory using Redis ?
Then we run a cornjob using WP-CLI to sync the post views count in Redis to the WordPress database.

Redis Post Views was born.