The size of storage has continued doubling with surprising regularity. Not quite Moore's Law-ish, but close. For 7200RPM SAS drives:
2009: 600GB drives in common use.
2010: 1TB drives in common use.
2011: 2TB drives in common use.
2012: 3TB drives in common use.
2013: 4TB drives shipped, not quite common.
2014: 6TB drives are shipping Real Soon Now (gotta get the cash out of the new 4TB drives)
2015: 6TB drives will be common.
Today's average single-rack storage appliance runs a little over half a petabyte raw capacity, and three-quarter petabyte single-racks are shipping today. I think we'll see "a petabyte in 1 rack" by year-end 2014 as 6TB 7200RPM disks start arriving (looks like we'll be skipping 5TB completely). Where I work, filesystems still tend to be smaller than that, more-or-less governed by the compressed size of tape that services them. So an average filesystem runs about 2TB-17TB depending on the tape tech backing it up. To back up a 17TB filesystem on a single tape still takes about 15-16 hours; to transfer it onto another hard drive, still longer!
What's a good brand of tape drive for a home-user?
For most, the answer is "none". Use a cloud service to store your critical data, or a second hard drive with Time Machine or something like that. The Cloud service provider will do tape backup of critical data (even Google does!) to cover disastrous situations which can and have occurred. If you're dead-set on tape backup at home, any recent table-top LTO5 or LTO6 drive (typical cost: $1,500-$3,000) will fit the bill. Media cost is pretty trivial after that initial investment, less than $30 for 3TB. It's this high initial-investment cost that convinces people "tape is expensive". The initial cost layout is prohibitive for some home users. But let's say you buy ten 4TB hard drives; you've spent $4,000 for 40TB (late 2013 prices), and typically have to worry about ongoing power costs & failure rates for those drives (MTBF means you have something like a 1 in 4 chance of one of those drives failing each year). For a thousand bucks, you can buy about 33 LTO5 tapes for something like 100TB of capacity. Different costs depending on your needs.
Where I work now I'm far away from that, and we cannot think of anything but 24x7x365 ops, so restore is a euphemism for failure.
Ditto. The ability to restore data is required for disasters and an "oops". The latter you can mostly prevent through sound policy, the former you work around after-the-fact. Even in a 24x7x365 environment, you can't totally prevent disasters -- human-caused and otherwise -- from occurring. Recovery plans that don't include tape typically have vastly higher costs, both initial and ongoing. Tape is a speedy cost-saving measure for large enterprise that provides some unique advantages, but is not a complete DR solution by itself! StorageTek has some pretty amazing products to allow tiered storage services that leverage tape for infrequently-accessed data. Check into it; it provides VERY strong support for 24x7x365 operation while dramatically reducing storage cost, and is very transparent for users.
Your first-tier storage is hard drive based, right? Tape is only a backup. How can hard disk not be fast enough?
We do massive data dumps on a regular basis, and I was typing quickly. I probably should have said, "For our needs, hard disks are extremely inconvenient and their throughput is too slow individually to suit.". Good catch.
$32 a TB never count compression, 8.5TB with the newer tapes/heads and max "feature" not sure one price as it's a sole vendor product I wont go near it unless it's the only option.
One vendor for the drives -- Oracle -- but many, many vendors for the tapes, including several aftermarket licensees.
For fast, gigantic storage at 250Mbyte/sec/drive or faster, at present the StorageTek T10K series sure seems to be the only option.
So 8.5TB raw for $160 for the same media = $18.83/TB. A bit less than three bucks a terabyte more. Compared to hard drive cost in 4TB drives of about $100/TB, that's still a hell of a deal!
Late 2013 pricing.
4TB hard drive: around $400
5TB tape: around $160
8.5TB tape (same media as 5TB, newer drive): still about $160
Cost per terabyte of disk: about $100.
Cost per terabyte of tape: about $19
I'm ignoring the cost of the tape drive, just like I'm ignoring the cost of the head(s) involved in NAS/SAN storage.
To fix your quote to be in line with reality:
Glacier is cold storage; the drives are only spinning when they are filled, when retrieving, and when scrubbing / consolidating. Just like tape but at least five times more expensive.
I'd love to see a Petabyte-Scale Tape Storage System that looked something like this...
You're thinking way, way, way too small. One of my tape silos a few feet away from me holds about 135 petabytes, and if we bought some expansion cabinets it would hold enormously more than that.
IMHO, a SL8500 silo with dozens of robots shuffling tapes around under the LED lights looks way cooler than a pair of spinning reels. Here's a small sample: http://www.youtube.com/watch?v=OpVnk_GeCaw
Tape is slow, expensive, proprietary and unreliable.
The only people who still use it are those who have to, or idiots with money to burn.
Fact check on the troll.
"Tape is slow". Absolutely false for throughput; true only for IOPS. A modern tape is much faster than a modern hard drive. That's the point of the article, and my personal experience as well. Random I/O to/from tape drives is incredibly slow, but no hard drive can touch a modern tape drive's throughput. It's the reason LHC uses it.
"Tape is expensive": True only in a non-ROI sense, therefore mostly false. You'll find a modern, large tape silo of equivalent capacity to a modern, large storage appliance usually works out much cheaper both in initial cost and cost over time if you intend to use the hardware for at least three to five years. That said, the cost of admission to the world of enterprise tape is pretty high; it's the ongoing costs that are much lower than hard drives.
"Tape is Proprietary": Both true and false. LTO is an open (licensable) standard, but the fastest/largest tape drives on the planet are typically proprietary right now, because being the fastest/largest causes more sales, and therefore funds innovation in faster/larger tape technology.
"The only people who still use it are those who have to...": False. There are many, many use cases for tape where it is not a requirement, but is just more convenient, reliable, faster, and less expensive than a hard-disk solution. I could list them, but, well, you're a troll and I don't want to type much more.
"The only people who still use it are... [those] with money to burn.": False. ROI is what drives most of our tape purchases, and we save an enormous amount of money by using tape in appropriate scenarios. Hard disks are appropriate for some use cases, tapes are mandatory or just a smart purchase in others.
There are 8.5TB uncompressed capacity tapes in enterprise use right now.
I work for the company that makes those 8.5TB uncompressed drives. Even our internal use is quite limited at present; demand vastly outstrips supply, and they are quite hard to get!
For the time being, we're still using the 5TB uncompressed/10TB compressed T10K "C" drives with T10K T2 tapes. Still the fastest, largest tapes on the market outside of their newer, younger brother, and worth every penny!
Tape never died in enterprise use. Its use as a desktop backup device, though, certainly is very limited now compared to the day when many new workstations shipped with a built-in tape drive to back up the disk...
Two can Live as Cheaply as One for Half as Long. -- Howard Kandel
