TLDR;
Today, a modern tape cartridge can hold 15 terabytes. And a single robotic tape library can contain up to 278 petabytes of data.
Today, a modern tape cartridge can hold 15 terabytes. And a single robotic tape library can contain up to 278 petabytes of data.
To be honest I never really understood the main reason for adding compression, especially since you can compress individual files far better using existing algorithms and then write those to tape. It must be a marketing thing.
The 10TB tape I found was "IBM 3592 JD Advanced Data Tape Cartridge 10TB/30TB (2727263)"
https://spectralogic.com/features/ts1155-technology-tape-dri...
Current 14TB disks are around 1000 gbit per square inch or 166 times denser.
Sure you need a motor, seek head, etc. All about the size of a tape. But you don't need a robot or tape vault either.
Seems unclear where the cross over for tape vs disk is. Especially when you use things like a backblaze storage pod and spin down disks when not needed to avoid the heat, power, and wear and tear.
Does make one wonder why not disk robots? The disks are the same size, support random access, and can be hot swapped.
I dug around and couldn't find a price on a 15TB tape, or even what it was called.
For long term storage, it's unlikely that disks will last as long as tapes.
All the electronic and mechanical components of a disk drive must still work in order for you to be able to retrieve data, and it's somewhat likely that if you just stick a drive on a shelf for ten years some percent won't be working afterwards.
For tapes, the separation of electronics from the actual storage medium itself means better maintainability; you can rpelace the tape drive without touching the cartridges.
Because a tape is relatively cheap, the drive is not. With a hard drive robot you lose the (small) cost of a SATA/SAS controller per drive, but you add the cost of the robot. If you're going to get disks you might as well just hook them up.