Comment by tjoff | Hacker News Reader

Comment by tjoff | Hacker News Reader

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I get 9 months at 20 MBit/s [1] which is kind of low for a blu-ray[2] or a high-end consumer camera, today.

I find it kind of difficult discussing 60 TB since it will be soo faar in the future. By then we will at least have 4k and probably a bitrate in ~100 MBit/s (since the cap is at 50 MBit/s today that is aiming low but there will probably be a limit where you say that it is enough (then again, 3D imagery could potentially demand much more)), a small drive (same density but ~2") would hold about 2 weeks of footage which IMO sounds reasonable for a camera in an age where you don't have to compromise that much.

It will put some constraints on usage patterns, but I don't feel that 60 TB will be that much more data than 4 TB is today. Sure, for text and audio you basically will have an infinite amount of space (as a consumer) but that is the case even today. 60 TB is only 15 times more than we have to day in a single drive, and it will take many many years to get there. And I can barely fit my grandfathers VHS camera tapes on a 4 TB drive today, and since I want some redundancy 4 TB isn't enough for even that.

1. http://www.wolframalpha.com/input/?i=60+TB+at+20+Mb%2Fs

2. http://forum.blu-ray.com/showthread.php?t=3338

> I get 9 months at 20 MBit/s [1] which is kind of low for a blu-ray

Blu-Ray bitrates are bloated for various reasons, like older encoders, film transfer, and a lack of anything better to do with the space. You don't need 20mbps with modern H.264 High encoders, it's just a waste. Anything past 10 is at best questionable

> By then we will at least have 4k and probably a bitrate in ~100 MBit/s

Even if 50mbps were something that we would ever need at 1080p (it's not), 4k would not justify a doubling in compressed size, there is no reason to have 100mbps compressed video.

4k is also way beyond reasonable for home display. Just 3840x2160 on a 60" display would be something like 23 arc seconds at 3 meters, you physically cannot see that.

> 60 TB is only 15 times more than we have to day in a single drive

4TB is already orders of magnitude more than most workloads will ever need. I was using video to demonstrate the absurdity of thinking typical workloads would actively use 60TB, because it's not a typical workload, it's a worst-case scenario.

"Ever" is a very long time. I'm sure you're also familiar with the Bill Gates quote

While I agree that there are diminishing returns when increasing the bitrate for modern encoders there certainly is a noticeable difference between 20 Mbit/s and 10 Mbit/s.

We would need those high-resolution displays if we ever want to be able to show off pictures decently, and we have (finally) just begun to experiment with high-resolution displays. 4k displays are already being demoed.

My point was that 60 TB vs. 4 TB, given the time difference, isn't such a big deal. Biggest hurdle is to get a stable COW-filesystem. But as today SSDs will rule the workstation (and pretty much everywhere you value performance) and SSDs have much bigger technical challenges to get that big.

Regular spinning harddrives will thus only be used where you have a untypical workload requiring lots of data.

> Blu-Ray bitrates are bloated for various reasons, like older encoders, film transfer, and a lack of anything better to do with the space. You don't need 20mbps with modern H.264 High encoders, it's just a waste. Anything past 10 is at best questionable

But most people won't want the hassle of re-encoding the data they receive. If it takes up twice as much storage, so what? A lot of people will buy that 60TB drive instead of a 30TB one.

> Even if 50mbps were something that we would ever need at 1080p (it's not), 4k would not justify a doubling in compressed size, there is no reason to have 100mbps compressed video.

So consider 4K + twice the frames to handle 3D + doubled framerate. That's 16 times the amount of uncompressed pixels. And I'm not convinced that's the upper bound of the amount of raw data we'll see.

It's not that long ago you'd have been called crazy if you suggested we'd need anything beyond 1080p, and a lot of people were questioning whether HD would ever get any traction.

> 4k is also way beyond reasonable for home display. Just 3840x2160 on a 60" display would be something like 23 arc seconds at 3 meters, you physically cannot see that.

I know people with projectors. 60" is by no means the upper bound on size people will want. 100"-150" maybe.

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