How the LHC Is Reviving Magnetic Tape 267
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samzenpus
from the what's-old-is-new dept.
from the what's-old-is-new dept.
sandbagger writes "The Large Hadron Collider is the world's biggest science experiment. When spinning, it reportedly generates up to six gigs of data per second. Today's six-terabyte tape cartridges fill rapidly when you're creating that amount of material. The Economist reports that despite the advances in SSDs and hard drives, tape still seems to be the way to go when you need to store massive amounts of digital assets."
Re:Never underestimate the bandwidth (Score:5, Interesting)
It's also interesting to see the advances in tape reading technology that they are striving for - it sounds as if it will keep pace with HD and SSD technology to keep staying relevant.
Re:but what about cheap disk? (Score:4, Interesting)
It depends on the optical disc. If you fork out the money for an archival media like gold CDs or DVDs, then you can probably expect something like 20 to 40 years. All in all, from what I've read, tape still is king in long term storage.
Re:Never underestimate the bandwidth (Score:5, Interesting)
Cheapest, sort of.
The price of storage roughly follows the y=mx+c linear graph: m is the cost of the media, while c is the cost of the equipment needed to access it.
For hard drives, it's easy: c=0. A drive is self-contained.
For tape, c is large (Up to several thousand pounds for one tape drive), but m is smaller (Tape, purchased in bulk, is cheap).
So if you're storing a small amount of data, a rack full of hard drives is cheaper. For larger amounts, tape is cheaper.
This ignores issues of ease of access and management software.
Gmail is backed up to tape (Score:4, Interesting)
A couple of years ago, Google restored lost gmail from tape [blogspot.com]. I'd expect that even with deduplication they must use a phenomonal amount of tape.
Consumer vs enterprise tape technology (Score:4, Interesting)
I've worked as a tape monkey in a large facility (Camp Foster RASC, Okinawa, circa 1989-90), so I know tapes do work well in the enterprise, but my experience with tapes in the consumer space in the 90s was anything but good. 90% of the tape backups made (using several different formats) using consumer-grade systems were corrupt and worthless.
We took great care with the tapes, but when we checked them (thankfully never needed them, except one occasion), they were mostly all bad.
Optical isn't much more reassuring as a backup media, given that optical discs tend to degrade over time.
If somebody has a tape system that can store terabytes on a cartridge, reliably, for say... $10/TB or less, and the system costs less than $200, I'd look at it, though. Otherwise, it is still more worthwhile just to use hard drives to back up data (even at their inflated prices)
Re:Never underestimate the bandwidth (Score:5, Interesting)
I used to work on data taking for the CMS detector at the LHC. We were using Storagetek tape silos [http://computing.fnal.gov/cdtracks/2009/january/images/robot.jpg [fnal.gov]] for long-term storage of data at Tier1.
Tape allows for cheaper storage and large capacities, but you're then fighting contention issues (there are only so many robotic arms and tape drives for your tape library) as well as having data on tapes go bad without knowing it. When data is on disk, I can at least verify it immediately. Bit rot is definitely alive and well on tape.
Re:Never underestimate the bandwidth (Score:4, Interesting)
These drives can even be too fast. The drives do speed matching, but they have a minimum speed, below that they start shoe-shining.
Er, "shoe-shining"? What do you mean?