I shared a link from NPR Tiny Desk but there was no image preview or video embed. After investigating this I learned that when you do that, each instance picks up the link and individually retrieves the link preview nearly simultaneously. For gargantuan sites like YT or Reddit, this is a trivial amount of traffic and not a problem, but for smaller sites like NPR this results in a sort of botnet DDOS attack on the site’s servers. More here. Another example here . For that reason, NPR has blocked Fediverse servers like Mastodon.
I have experienced this on my personal server as well (DDOS), but at the time didn’t know why, exactly.
This isn’t the end of the world, but certainly is not great and hurts engagement with the content. Is there a solution for this? Perhaps using some sort of webtorrent service like PeerTube where they just fetch the information from another fediverse server instead of the source server? Maybe fetching embeds client-side? At least that would stagger the requests.
I don’t think compute resources should be an issue, if anything it saves other instances resources.
As far as I understand, right now, all instances are fetching this data individually, so they all have the same compute load from this. Doing it on one and sending it along with federation should keep resource useage pretty much the same on the originating instance, and less for all others.
This would still increase bandwidth of course, but at least with all VPS providers I have used, bandwith is pretty cheap.