5 ms·

Tape would be perfect because people don't tend to skip through movies to random points. At least I don't.

toast0 3y ago
You might not, but some people do. And disc based formats assume reasonable seek times for menus. Plus if you're storing multiple movies on a tape, you still need to seek to the beginning of the one you want. A 100-disc changer or an archive of discs onto rotational hard drives would be a better experience.
- jasomill 3y ago
  Seek time wouldn't necessarily be a deal killer, as you could store chunks of movies as files in a structure similar (or identical) to LTFS[1] and have average seek times from tape load less than a minute and local seeks (forward/back chapter/minute/etc.) somewhere between a few seconds and instantaneous, depending on chapter length and how much cache RAM you're willing to throw at the problem. Bear in mind that tape movement in an LTO drive is many times faster than a naïve tape capacity / transfer rate calculation might suggest, as LTO drives require anywhere from a few dozen to a couple hundred head passes to read/write a full tape, and seek to a given logical block number considerably faster than they can read or write. The bigger problem I see with tape library vs. RAID for consumer movie storage is cost. Even if we assume economies of scale would drive the cost of LTO-9 drives down to, say, $1,000, you'd still need to store a lot of movies for the cost of LTO-9 drive + library robotics + tapes to approach the cost of large capacity hard drives + additional cabling and interface electronics, given that $1,000 will buy enough hard drive capacity to (non-redundantly) store over 1,000 50 GB UHD Blu-ray movies. [1] https://en.wikipedia.org/wiki/Linear_Tape_File_System https://en.wikipedia.org/wiki/Linear_Tape_File_System
  - sschueller 3y ago
    Is the cost of LTO due to the technology or the small market and a few large players taking advantage of that?

You might not, but some people do. And disc based formats assume reasonable seek times for menus. Plus if you're storing multiple movies on a tape, you still need to seek to the beginning of the one you want. A 100-disc changer or an archive of discs onto rotational hard drives would be a better experience.

jasomill 3y ago
Seek time wouldn't necessarily be a deal killer, as you could store chunks of movies as files in a structure similar (or identical) to LTFS[1] and have average seek times from tape load less than a minute and local seeks (forward/back chapter/minute/etc.) somewhere between a few seconds and instantaneous, depending on chapter length and how much cache RAM you're willing to throw at the problem. Bear in mind that tape movement in an LTO drive is many times faster than a naïve tape capacity / transfer rate calculation might suggest, as LTO drives require anywhere from a few dozen to a couple hundred head passes to read/write a full tape, and seek to a given logical block number considerably faster than they can read or write. The bigger problem I see with tape library vs. RAID for consumer movie storage is cost. Even if we assume economies of scale would drive the cost of LTO-9 drives down to, say, $1,000, you'd still need to store a lot of movies for the cost of LTO-9 drive + library robotics + tapes to approach the cost of large capacity hard drives + additional cabling and interface electronics, given that $1,000 will buy enough hard drive capacity to (non-redundantly) store over 1,000 50 GB UHD Blu-ray movies. [1] https://en.wikipedia.org/wiki/Linear_Tape_File_System https://en.wikipedia.org/wiki/Linear_Tape_File_System
- sschueller 3y ago
  Is the cost of LTO due to the technology or the small market and a few large players taking advantage of that?