From what I can gather every follower gets an individual copy of every post sent to their server who either deduplicates it and stores it in their database or just stores the message per subscriber.

So if 10,000 people on server A subscribe to someone on server B then server B will send 10,000 duplicate messages to server A.

I hope I’m wrong but that’s what I’ve heard.

Reminds me of:

> This program posts news to thousands of machines throughout the entire civilized world. You message will cost the net hundreds if not thousands of dollars to send everywhere. Please be sure you know what you are doing.

From the rn usenet client, back in the day.

Maybe if more people thought this, a lot less posts would be made. I'm guessing that would be a net positive for society in general.

> Maybe if more people thought this, a lot less posts would be made

This is why we can't have nice things: https://en.wikipedia.org/wiki/Laurence_Canter_and_Martha_Sie...

Oh my! I’d heard ActivityPub was chatty but haven’t looked into the details. This, if true, sounds … not good.

Anyone with expertise here who can speak to the scaling of ActivityPub?

The size of an ActivityPub payload overhead is minimal.

On each individual server they are ideally saved based on their unique identifier (which are RFC3987 IRIs) and I doubt that there is any software that will do it individually for each inbox instead of storing one copy to which each inbox links to.

To minimize even this, each server can store just the IRI(which is mandated to be de-referenceable) and load the payload when prompted by UI. I doubt that anyone does this also.

Yes that makes sense! Thanks!

Why are tech people so behind mastodon? If this is true this sounds incredibly worrying to scale; to the point where mastodon is limiting it's own growth potential

If. Did you research if this was true before posting a knee jerk reaction to something that might not be true? If not, you are no better than the person that posted the misleading comment.

Remember there's a fair bit of speculation here, I just thoughtlessly blasted my question here without researching (not sure where to start, tbh) and UncleEntity didn't seem too sure about the duplicated/redundant requests. It's entirely possible that Mastodon doesn't have this problem

I wish people wouldn't spread rumors like this. ActivityPub does have shared inboxes[0] and Mastodon does use them[1], so no duplicate messages will be sent in your example.

[0] https://www.w3.org/TR/activitypub/#x7-1-3-shared-inbox-deliv...

[1] https://github.com/mastodon/mastodon/blob/a5a00d7f7adff5e0af...

I mainly use twitter to keep tabs on some artists and none of them want to move. Reading this, maybe it is for the best. My follows would create a lot of overhead for wherever it is I park my account compared to someone who just participates in text.

I have my own instance, and it eats disk space, in a fun and sometimes difficult to recover way.

It caches all media that you view, and I assume it might prefetch stuff to. It has a tool that prunes out old cached images and such. However that script isn't setup to run automatically (or if it is, its far too loosey-goosey)

However the biggest killer is that it doesn't clear cached user page header images. Here is the output of my cache. Headers are not cleaned, and need to be deleted manually.

  Attachments: 1.43 GB (8.19 MB local)
  Custom emoji: 61.9 MB (0 Bytes local)
  Preview cards: 344 MB
  Avatars: 3.01 GB (71.7 KB local)
  Headers: 6.69 GB (172 KB local)
  Backups: 0 Bytes
  Imports: 0 Bytes
  Settings: 36.2 KB