> Certainly makes me wonder if those are on a more prioritized and entirely separate infra and SLA that is designed to be more resilient and highly available.
There's absolutely no doubt that the ads are served differently. Think about it this way:
- Ads: Small number, each served to many people, funded with real cash, but you can't get the cash if you don't serve the ads.
- Photos: Large number, each served to few people, funded by money left over from ads, and if you don't serve them your (non-paying) customers get frustrated.
My guess is that ads is funded well enough that they can run at lower resource utilization, and much more effort is made to run photos at high resource utilization. That's how I'd run it.
Ads:. Conduct an auction in milliseconds between hundreds of parties between hundreds of millions of ad creatives with lots of very large in-memory machine learning systems, all to decide which ad to serve to maximize revenue.
In systems like this, you tend to want to maximise some other outcome than revenue (like clicks or conversions). In general, both GOOG and FB make money out of DR advertisers who care about this, so you tend to make more money if you optimise for the thing they care about (revenue goes up as a second-order effect).
There's absolutely no doubt that the ads are served differently. Think about it this way:
- Ads: Small number, each served to many people, funded with real cash, but you can't get the cash if you don't serve the ads.
- Photos: Large number, each served to few people, funded by money left over from ads, and if you don't serve them your (non-paying) customers get frustrated.
My guess is that ads is funded well enough that they can run at lower resource utilization, and much more effort is made to run photos at high resource utilization. That's how I'd run it.