Single Request Architecture (SRA) is a way to send ad requests for all the defined ad units together rather than sending requests for ad units individually. If you use Google Ad Manager, you should’ve realized while generating the GPT tag, you’ll have the ability to enable/disable SRA.
Google advises publishers to use SRA for performance reasons. Apparently, if you have 5 ad units on the page, you can send all the requests at once when the page loads instead of sending ad requests separately.
Lazy Loading:
If you are lazy loading ads, then you know elements are loaded (images, ads, and iframes) on the pages only when users scroll them into view. In other words, you can’t have both SRA and lazy loading.
Dynamically Loading ads:
In addition, if you are dynamically rendering new ad units based on scroll depth (or if you aren’t defining ad units beforehand in the header), then SRA implementation isn’t possible. The same applies if you want to load only certain ad units on the page — SRA will lead to errors.
Our suggestion is to assess the current setup and then decide whether to enable it or not.