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Comment by wronglebowski | Hacker News Reader

It seems quite unfortunate we’re coming up the other side of the U shaped price graph for HDD technology. From collusion between the three manufacturers and a consistent push towards flash it’s unlikely we’ll see any further reductions in price per GB without major performance hits like SMR.

This wouldn’t be a problem if flash were cheap enough in the volumes required for archival level storage, but it isn’t. Flash storage is actually going up this year as demand continues to increase.

I suspect there’s no ready answer for those that hoard data now or in the future.

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NAND is down to $.12/GB, and HDDs are at $.02 (source: checked newegg just now).

Hard disk raid rebuild is basically an offline process for wide stripes and raid 6. Assume 2x parity overhead (eg 2 raid one disks, or a 2+2 setup) for hard disks, and close to zero for NAND (5+2) and SSDs are 3-4x more expensive than spinning disk.

Also, you can be more aggressive with compression and dedup with NAND, and it takes up less power, cooling and case space.

So, NAND is somewhere between 4x-1x the price of disk for archival. At scale, to get to 4x you’re probably talking about nearline retrieval.

Flash storage is lacking the longevity of HDDs though. They were certainly not suitable for archival the last time I checked.

Neither are hard drives: if you really care about it, you need multiple copies which are regularly accessed. Putting a box on the shelf for years is playing with fire.

True, but still, there was significant difference between HDD and Flash lifetimes.

Not enough that I’d trust it with anything I cared about. Drives have many mechanical failure modes, the higher density ones are more exposed to media degradation, and you have different environmental concerns – e.g. flash will survive water better.

The best answer is multiple copies, preferably on different media: hedge your bets and use both, and verify it periodically so you’d know before your “working” drive throws a ton of errors when you actually try to read the data.

Well, the only thing I trust is my RAIDed ZFS with weekly scrubbing. However, that's not a backup solution. Spinning rust doesn't degrade materially over time when powered off but Flash certainly does.

If tape was cheaper I'd consider that.

> Spinning rust doesn't degrade materially over time when powered off but Flash certainly does.

Magnetic media does degrade, moving parts freeze or fail in other ways, and the circuitry can also fail. It’s often possible recover that at some cost but it’s much more expensive than n > 1 copies.

Yes, true, but for a hard disk at _rest_ (in a controlled environment) I posit it's failure distribution over time is dramatically favorable to Flash (especially TLC and QLC). I feel pretty comfortable keeping a ZFS drive pair (= mirrored) on the shelf for a decode or two whereas I'd abandon all hope for a modern SSD in the same conditions.

EDIT: typo

You sure about that? I remember reading comments like this when drives seemed to be "stuck" in the 300gb range, and again when 1-2tb was about as big as you could get for a while. Now we have 16TB drives; so is there really some issue for those who want to hoard?

Honestly, how big is your personal hoard anyway if a few 16TB drives won't cover it? Isn't it the case that at some point you will have amassed more media than you could possibly consume?

In my opinion from the previous price fixing scandals and no real competition between the few major suppliers there's very little driving innovation in this space. Perhaps the major suppliers will get better deals or bigger drives but there's no reason for the players in the market to make a product consumers can buy more appealing. We're such a small part of the market and have such little choice.

bluray quality video is about 13GB/hr for 1080p or 33GB/hr for 4K. it's cost prohibitive for people to accumulate a huge amount of this content legally, but torrents are still a thing. it adds up really fast if you aren't willing to prune your collection.

there isn't currently a ton of 4K content available, but there's lots of 1080p. if you rip/download enough bluray 1080p to watch an hour every night, that's almost 5TB per year right there. if there were enough 4K content to support your habit, it would be more than 12TB a year.

Assume average movie length of 90 minutes and 4k Blu-ray price of $20 (I don't buy physical Blu-ray's but found some year or two old recent marvel movies cost about that much - new releases cost more, typical boxsets come out as costing less per item)

So that's 50GB/20$. Or $400/TB. So the content to fill those hard drives is about 5x the drives yourself. So it's not infeasible that people could fill them with legal movies.

Not to mention TV shows, video games, and content that is much denser in GB/$.

When my kids were young and could ruin a DVD just by taking it out of the case, I put together a home theater PC and ripped all the kids DVDs to it. There's well over 100 movies on that disk, and I still have the original DVDs for backup.

My personal horde is a 9x16TB raid-6 yielding 101TiB usable.

"640K ought to be enough for anyone." - Unknown

It's likely that 16TB won't keep up with further technological advances.

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