[stavros]

You don't have to actually pin things. Merely visiting will cache and rehost the files, and they will only be GCed at some later time. All pinning does is disable the GC for those files, which, as of a few months ago, weren't getting GCed at all anyway, so visiting something was equivalent to pinning it.

[MrEldritch]

"So unless for some reason I specifically think to help share some webpage or other, it'll just get auto-deleted from my machine when it cycles out of the cache" - my original post above.

I was thinking about that content effectively "linkrotting" away if nobody visits it for a while, say it's old posts on a blog or something. I suppose how big of an issue this really is comes down to how long stuff would tend to stay in that cache in a real, practical usage scenario. I guess I'd been assuming that it'd only be day or so, but it could be longer in practice, depending on how much space is actually allocated to the local cache and how much each individual bit of unique content takes up and how many such unique chunks of content will be downloaded per day, along with maybe some more complex factors besides first-in-first-out for deciding what to collect.

(I elaborated a little more about this below, when I thought about it kinda working like an automated torrent manager that made sure you maintained a decent seed ratio, didn't exceed an upload data cap, etc. and shuffled stuff out when it was taking up too much space or had hit a target ratio and wasn't going to be seeded anymore, with some prioritization for "is there anyone else seeding this", "is this a highly-demanded bit of content", etc.)

[MrEldritch]

And in any case, even though a centralized server is still needed for p. much any practical use case, it's not like that makes IPFS useless - it's still possible in principle for any given bit of content to stick around basically forever and its link to keep working, even if the server goes down, as long as other people want to save it.

Plus, even if almost nothing is going to really be truly dcentralized, it could make hosting a site a heck of a lot easier because the traffic you personally have to deal with may be drastically reduced, as popular content gets uploaded to the first users who can then share with later users. You only have to be the exclusive host of content that's accessed more rarely than the period it'd typically stick around in the cache of the last person to ask for it. (depending on whether or not that last person is currently online.)

(It's easy to imagine a case where short-term decentralized hosting from user caches could be almost entirely sufficient - say, an IPFS-based version of 4chan, where threads are inherently short-lived and temporary objects anyway, and only in the very slowest and least-populated boards would you have threads that are checked so infrequently that you couldn't rely on the currently online user caches to contain that content. You'd still need a central server to do things like spam filtering, user authentication (to make bans stick), and update the index of what files hashes and post hashes are in which threads and in which order, and which threads are currently alive on each board)