18TB hard drives made possible using table salt | Hacker News Reader

18TB hard drives made possible using table salt

geek.com

56 pointsukdm19 comments

Why must SSDs match the capacity of HDDs, but HDDs not have to match the latency and throughput of SSDs? Is it only because of the price premium SSDs carry?

I don't really see the 2 technologies in competition at this point. Even if there were 10 TB SSDs today almost nobody would buy them for personal use because of the price. Similarly if you need or want a fast disk HDDs aren't in the running at any capacity. I see the technologies as complementary right now, and probably for several years out.

If the price of SSDs ever falls to match HDDs then they would be in competition.

Because I can only afford a 120GB SSD and have at least that much on my HDD already.

Plus reliability is an issue. Any improvement of SSD reliability is a huge gain for them.

You can easily get a 10x gain in SSD reliability by using SLC instead of MLC memory. All for only 10x the cost of MLC.

Are there actual reports of unreliable SSDs that are not anecdotal? I have yet to see any evidence that they are worse than HDDs. That doesn't mean it isn't out there but I haven't seen any "reports" that are more than anecdotal FUD.

In the consumer space HDDs have a pretty poor track record.

The "safe" lifespan of an SSD, this is just hear-say so don't criticize that, is around 1 year. Any more you get is just a bonus. I think I read that on codinghorror.com...

Anyway, I've got a Mac which probably doesn't support the latest, greatest SSD features. And my experience with HDDs says an average of 5 years life is pretty easy to attain. Therefore, for someone who needs cheap space with decent lifespan the HDD is the obvious answer.

And at 10x the cost for a reliable SSD ... sorry. I may be a programmer but I do draw the line at expensive stuff (I don't even on an iPad or iPod, my Mac is almost 2gen old...).

> and a greater challenge for SSDs trying to catch up with the amount of storage on offer.

This technology is pretty much exclusively for backups, no? Not really the competitive space for SSDs. With only a single read/write head and 18TB of information on a drive, you're looking at an enormous performance bottleneck.

increasing plate density has been the primary driver of the increased stream performance of the HDDs - with the same rotation speed the more dense plate results in the more bits to fly under the head. Random IO of course is a different beast. Though is you look at the data filling the disks - like movies - it is more about stream not random.

The headline was extremely confusing to me until I realized that the table salt they were referring to was NaCl, not a randomized bit sequence padded on to a string before hash.

Your comment confused me as well for a moment as I tried to grasp how Native Client might help with this.

My first HDD was 40 meg (in a ~$6000 inflation adjusted computer). For the same price it's eminently feasible to get a system (computer + a NAS or three) with 40 TB. If my calculations aren't wrong that's enough for over ~77.6 years (24/7) worth of compressed audio @ 128 kB/s.

How much is that (the price of the 40meg HDD) as a percentage of your income now? Is it the same as a similar specialist back then?

This was a home computer, but it was still a significant purchase for dual income professionals. 1989 release price in the USA with the same upgrades we had US$2899 (without monitor?), then the screen (14"), software, printer and "outside the USA price hike" must have made up the other ~$1101. I get far bigger usb sticks for free at conferences these days. Raspberry Pi + a screen or a bottom of the line netbook for $200 is hundreds of times more powerful. 133 times more powerful if we just talk 1989-mhz (12mhz) to 2011-mhz (atom 1.6gighz), which is inaccurate. So things have gotten about 30 times cheaper and insanely more powerful.

Edit: to address your question more directly it was like a "second hand car" purchase maybe ~10% median annual household income vs ~0.3% these days for the netbook. This is all back of the envelope stuff though.

Back in 1991 we took out a special insurance policy to cover the computers and hardware in our house (two professional coders). Just the hardware came to $22,000. (We figured the software was just licenses which couldn't effectively be stolen.)

Of course if you have 40TB you might also want to have uncompressed audio & also have video.

Every single hard drive I got so far, no matter how big it seemed at the time, I managed to fill with data. Generated data is like a gas, it will just expand to fill in the available space.

For most people that space is taken up by caching other peoples work, AKA movies, programs, music etc. After I could stream HD content over my internet connection I feel little need to keep a local copy of most of these so I have actually started to use less HDD over the two years.

It's still feels odd, I filled up a 750GB HDD then I got a 240 GB SSD and a 2TB HDD and yet I find I am useing less HDD now than before the upgrade.

My first HDD was on a Commodore Amiga and was a mighty 60Mb.

Mine was 6Mb. I had to build my own interface card and I/O driver for it (for my Heathkit H11).

And it was still enormously useful over those floppies.

I love to be reminded that my all my precious data is stored on little 7nm magnetic grains...

As with all hardware predictions, I'll take this one with a grain of salt.

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