What is the long-term storage plan for Lemmy instances?
What is the long-term storage plan for Lemmy instances?
Over time, Lemmy instances are going to keep aquiring more, and more data. Even if, in the best case, they are not caching content and they are just storing the data posted to communities local to the server, there will still be a virtually limitless growth in server storage requirements. Eventually, it may get to a point where it is no longer economically feesible to host all of the infrastructure to keep expanding the server's storage. What happens at this point? Will servers begin to periodically purge old content? I have concerns that there will be a permanent horizon (as Lemmy becomes more popular, the rate of growth in storage requirements will also increase, thereby reducing the distance to this horizon) over which old -- and still very useful -- data will cease to exist. Is there any plan to archive this old data?
Pictrs 0.4 recently added support for object storage. This is fantastic, because object storage is dirt cheap compared to traditional block storage (like a VM filesystem). This helps a lot for image storage, which is a large part of the problem, but it's not the whole problem.
I know Lemmy uses Postgres for everything else, but they should really invest time into moving towards something more sustainable for long term/permanent hosting. Paid Postgres services are obscenely upcharged and prohibitively expensive, so that's not an option.
I'm armchair architecting here so I'm not sure what that would look like for Lemmy (Cloudflare KV? Redis?)
Still, even my own private instance has been growing at a rate of about 700MB per day, and I don't even subscribe to that many things. I can't imagine what the major instances are dealing with. This isn't sustainable unless we want to start purging old data, which will kill Lemmy long term.
EDIT: Turns out ~90% of my Lemmy data is just for debugging and not needed:
https://github.com/LemmyNet/lemmy/issues/3103#issuecomment-1631643416
74I'm not really sure that a K/V service is a more scalable option than Postgres for storing text posts and the like. If you're not performing complex queries or requiring microsecond latencies then Postgres doesn't require that much compute or memory.
People can get unnecessary scared of relational databases if they've had bad experiences with databases that are used poorly, but attempting to force relational data into a K/V can lead to the application layer essentially just doing a less efficient job of the same types of queries that the database would normally handle. Maybe there'll be some future need to offload post and comment bodies into object storage or something but that seems incredibly premature.
Object storage for pictrs is definitely a fantastic addition, though.
16The 700MB are the postgres data or everything including the images?
I'm under the impression that text should be very cheap to store inside postgres.
9On average, 500MB is Postgres, 200MB is Pictrs thumbnails. Postgres is growing faster than Pictrs is.
3My local instance that I run for myself is about a week old. Has 2.5G in pictrs, 609M in postgres. One of those things that'll vary for every setup
2
The largest table holds data that is only needed by Lemmy briefly. There is a scheduled job to clear it... Every 6 months. There are active discussions on how best to handle this.
On my instance I've set a cronjob to delete everything but the most recent 100k rows of that table every hour.
6It would be greater if it can also leverage IPFS. So we can have unique identifiers per media object and hence deduplication in a P2P network which in my opinion is more federvise affinitive. I have been thinking of making such an alternative media backend for a while.
4There is a good writeup on how to do the migration here. I went through it myself since I host my tiny Lemmy instance on an AWS EC2 instance. It went pretty smoothly bu obviously larger instances will have to take a longer downtime to perform the migration.
3Hey, that's a Vultr guide! I use Vultr, thanks!
By the way, how are your costs on EC2? My understanding is that hosting on EC2 would be cost prohibitive from data transfer costs alone, not to mention their monthly rates for instances are pretty much always below the cost of a VPS.
Now if only someone could do this for the Postgres data. I wonder if S3FS would be able to handle the load of a running database, that would be a nice way to save costs.
4
AWS Postgres instances aren't that expensive, and they handle upgrades and backups for you.
That said, I'm interested in distributed storage, and maybe this fall/winter when I get some time off I'll try making a lemmy fork that's based on a distributed hash table. There are going to be a ton of issues (i.e. data will be immutable), but I have a few ideas on how to mitigate most of the issues I know about.
3Isn't it mostly pictures and movies taking up space, posts and comments that is just text doesn't take up much.
I would be fine with text is forever but pictures and movies are deleted after time.
3Just think of all those old, helpful forum posts from years past with tinypic and Photobucket links that are dead. I agree memes can probably die out after time but anything informative would be bad to lose imo
6For large instances pictures is probably the bigger consumer of space, but for small instances the database size is the bigger issue because of federation. Also, mass storage for media is cheap, fast storage for databases is not. With my host I can get 1TB of object storage for $5 a month. Attached NVMe storage is $1 per month per 10 GB.
For my small instance the database is almost 4x as large as pictrs, and growing fast.
5
I'm in a similar boat and I'm gaining about 300 MB/day on my small instance doesn't yet have any local communities.
2
One way to approach the geometric storage growth would be to not cache everything everywhere all at once. With 1000+ instances, storing an object in a few instances would be ok if others can pull it in on demand. Can use some typical caching methodology like use frequency, aging etc.
27This is a great idea. Instances will need eventually to agree to common storage areas, even if they dont all allow the same content on their instance. That savings would be huge in the long run.
4
Premature optimization is not good. Content here is not very storage intensive, so I would not yet make it to issue. Postgre can handle billions of rows when indexed right.
23Sounds like the federated instances should consider opening up for donations and paid features like comment awards and animated shit like Discord or Reddit.
22Permanently Deleted
42I liked Reddit Gold when that's all there was. A super-upvote conveying "I'd pay money for this posting".
The weird tiers they added later weren't an improvement on that but fine I guess and the stupid icon thingies they have now? They're horrible.So, I'd be in favour of something like the old Reddit Gold but I wonder how it could even work in the fediverse.
18
I worry that these sorts of things would end up turning the site into a popularity contest (or, well, more of a popularity contest than these sorts of sites already are. That being said, I'm quite proud of Lemmy, currently, as it appears to be resisting that). Also I'm not entirely sure how things like payed comment awards would work with everything being federated.
12Yeah, no. No to paid features. That's how we ended up with reddit.
11No, we ended up with Reddit from stupid top-down leadership stupidity. I have no problem with Reddit's awards and whatnot, I have a problem with them locking kicking out third party apps and limiting the mobile web experience.
If you don't like an instance's profit model, just move to another one or host your own. There are plenty to choose from, so competition will keep away the worst of it.
My preference is for monetary subscribers to get access to new features early and to get more of limited features (i.e. if everyone gets X awards to distribute/day, subs get 2X or something), but for features to eventually make their way to everyone else. This allows A/B testing in an interesting way while funding the project. Since the project is FOSS, individual instances can decide to roll them out to everyone or block usage of these optional features from other instances.
If instance admins will be paying hundreds per month for hosting, they should have some way outside of donations to recoup that cost (plus their time spent). I doubt anyone will get rich from it, but hopefully it'll be enough to help admins offset the costs.
3
I'd be ok with something like a "donor" flair.
6I think we could do some kind of profile badge if you donated. So it wouldn't influence the way people vote, only if you clicked on their profile will you see it.
3
May be lemmy.world Admins can answer this ? @michelleG
15The long term solution is something like IPFS object storage that's read only for everyone but the author instance. One copy of the data but all instances can read it and it's stored forever in a redundant medium with bitrot protection.
5Delete it all! The 'ol internet archive'll take care of it slaps hood
1Personally I think we should add a differentiation between the storage policies of content which is owned by your own instance and content that federates from other instances.
The former should be kept for a long time (forever?), while the latter can be cleared more regularly.
1Permanently Deleted
-1ie oldest postes && least liked First
This would pretty much automatically throw out all troubleshooting posts. These sorts of posts, very often, don't receive many likes, as that is not their purpose. On top of that, there has been many a time that I have been saved by finding some ancient forum post that solved my problem.
18Permanently Deleted
5The real takeaway here is that we are all bad at storing the kind of knowledge you’ll find in a troubleshooting post.
Perhaps there can be a Lemmy instance that scrapes and mirrors troubleshooting posts across other instances.
1So do I. And since there were no rule I didnt thumbs up the ancient but helpful content to keep it alive. Purging is not about censorship but to keep fragile communities alive by keeping above all their true value.
1
I m sure I won’t miss this post in one month or even one day.
Well, maybe you won't, but others might. That was the great thing about Reddit. Found a sub that might be interesting? Browse its top content of the last ten years and you'll see. Have a specific programming question? Google it with site:reddit.com and you'll likely find a good discussion on it. Reading on old interview somewhere and wonder if someone ever fact-checked that one statement there? The guys at Reddit likely have.
Even before the blackout it already happened way too often that you stumbled upon an interesting Reddit thread just to see that one of the central comments has been deliberately deleted by its author and so the whole thing gets less helpful. Would be a shame if the system itself would further delete even more content.
11That is why rules are set to keep content with true value. Else it's content archeology and as IRL you won't find everything untouched as it was.
0
Why are people downvoting this? It's just practical. If you don't reduce the amount of storage you use, the cost of storing will constantly and steadily rise, will donations or personal budgets keep up? Maybe on lemmy.world or other mega instances but it just won't be the case for everybody. I think purging old content is gonna be a reality eventually, even if it takes a really long time before it catches up to the larger instances. And it's going to be OK as long as, as this person suggested, the rules for purging old stuff is tenable for everybody.
For example, does lemmy.world, lemm.ee, and sh.itjust.works really NEED to keep each other's entire federated post history, in perpetuity? As these guys grow larger wouldn't it make sense to start purging very old duplicate content between them? Stuff that hasn't been accessed on the instance in, say, over a year? Mind you, I believe that before we get to this point, there will be other systems in place. For example, the Reddit archive sites were never run by Reddit, and they often contained ads or other monetization strategies. Donations can keep the most recent or relevant content up on the instances, but somebody somewhere is gonna have to pay for this content to stay out there. For all we know, it's gonna be fucking Google and their seemingly unlimited cache. For all we know, some person at Google is spending his 20% personal project time subscribing a bot to everything on the fediverse and collecting data for some kind of new search engine right this very second on Google's hardware.
Anyway, just some food for thought.
2People always assume they deserve to have stuff hosted on the internet forever for free. I'll donate a good chunk for my instance for sure, but I'm not going to be shelling out hundreds of dollars a month for it either.
If people care so much about it staying up forever they can start donating.
2