> Wouldn't this mean that if X is the total amount of consumed storage currently used, you still need 2.5 times X _additional_ unused storage across the swarm in which to hold the 2.5 distributed copies?
No. The first copy-equivalent is the original data.
And again, even that's only for bespoke personal data. As soon as you have a few people with a copy -- which is even the case for most "personal" files, because friends and family will have copies of your photos etc -- then you don't need any redundancy past the copies each person already has on their own device.
Moreover, cloud providers are already wasting more space than that. People have a copy of their data on their own devices, but also on the servers, and then the servers have at least one backup. That's three copy-equivalents already.
> If so do average people keep such amounts of free storage around?
Millions of people buy computers with 1+TB hard drives and then use less than 10% of the space.
And it's possible to use the free space without really depriving the owner of it, because you can set a minimum free space threshold and transfer data off the machine if it ever falls below that, so the space is only used if it would otherwise have been free space.
> No. The first copy-equivalent is the original data.
Ah, got it.
> Millions of people buy computers with 1+TB hard drives and then use less than 10% of the space.
See that's the bit that's weird to me. My OS drives are small SSD's and the spinning platters are all comfortably full.
I will say though, I'm replicating once onsite and once offsite so my own redundancy is pretty high. If I could get over the 'someone else having physical access' thing (I don't use cloud for most personal data) I suppose IPFS or equivalent would be cool.
> See that's the bit that's weird to me. My OS drives are small SSD's and the spinning platters are all comfortably full.
You have to remember that you know what you're doing. You know how much space you need and you know how to add more later, so you don't buy more than you need.
The typical person buys a 2TB hard drive because they have "thousands of photos" and the 2TB drive is only $15 more than the 0.5TB drive, even though "thousands of photos" consume like 0.005TB.
And they're rational to do it because they know they aren't good at predicting whether they will fill the smaller drive and it's worth $15 to hedge against the ordeal of adding more storage later.
Which means many people will buy a 2TB drive and use it to store 75GB of data.
No. The first copy-equivalent is the original data.
And again, even that's only for bespoke personal data. As soon as you have a few people with a copy -- which is even the case for most "personal" files, because friends and family will have copies of your photos etc -- then you don't need any redundancy past the copies each person already has on their own device.
Moreover, cloud providers are already wasting more space than that. People have a copy of their data on their own devices, but also on the servers, and then the servers have at least one backup. That's three copy-equivalents already.
> If so do average people keep such amounts of free storage around?
Millions of people buy computers with 1+TB hard drives and then use less than 10% of the space.
And it's possible to use the free space without really depriving the owner of it, because you can set a minimum free space threshold and transfer data off the machine if it ever falls below that, so the space is only used if it would otherwise have been free space.