Update when full page is loaded

Hi, I’d like to know if it’s possible to update prices and availability by page view but only after the whole page has been already loaded.

This way I could prevent long loading times before a page actually loads since I use many different offers on the same page.

I’ve looked into the plugin files and I noticed that the update function uses templated_redirect as hook. My idea is to use a script the loads a php file when the page has been fully loaded. Could give me some hints on how to properly call the update function ?

Thanks