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Seagate Overcomes Superparamagnetic Limit
Longinus writes "Yahoo! News is reporting that hard drive manufacturer Seagate has "overcome a significant challenge in magnetic memory with a new technology capable of achieving far beyond today's storage densities -- up to as great as 50 terabits per square inch. Currently, the highest storage densities hover around 50 gigabits per square inch, but Seagate said its heat-assisted magnetic recording (HAMR) technology could break through the so-called superparamagnetic limit -- a memory boundary based on data bits so small they become magnetically unstable." Perhaps the near future of storage technology lies, for now, not in nanotech or holography, but still in magnetic recording."
You were wrong even before this announcement. 2TB RAID arrays have been practical for quite a while.
Tarsnap: Online backups for the truly paranoid
A 40GB/platter drive (4 platters = 160GB) has a density of 80 gigabits/inch.
So, @ 50 terabits/inch, you could have ~25TB/platter hard drives, or about 100TB in the same form factor as the current maxtors.
G'damn.
-asparagus
Moore's Law only states that the density of switching elements (transistors) on a silicon substrate will double about every 18 months. Moore's Law emphatically does NOT state that computing power will double every 18 months.
:)
Recap:
Computing Power != Transistor Density
Just a quick clarification.
So at 50Tbit/in^2 that means that a 3.5" drive with 4 double sided platters might hold
.5" hole)
:)
Area of disk (considering
9.62 - 0.196 = 9.424 in^2
8 Data surfaces
8 * 9.424 =~ 75 in^2
Total data storage:
75 * 50 / 8 = 471 Terabytes!
471 TB = 517869976682496 bytes
Bits needed to address this number of bytes:
ceil (ln (517869976682496) / ln (2)) = 49
And thankfully so long as we have a 64 bit architecture then reiserfs will happily work
It's been done for about 2 decades. They are used in database apps for accelerating the transaction log partitions as that can quickly become the limiting factor if the rest of the database is spread over a hundred or more spindles. They are in fact a niche product and because of their target audience are both tested to hell and mega expensive, since by their very definition the are used in the largest of database application where the most is at stake.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Scientific American had a feature article a while back that explained the superparamagnetic effect, as well as the holographic storage technology that the story poster referred to.
The article was also featured on Slashdot.
State of the art is ATA/ATAPI-6 a.k.a. "Big Drive". It supports 48-bit addressing. That's 48-bit sector addressing, so the maximum size of a disk is 144 Petabytes. This standard also supports transferring 32MB of data in a single I/O. This is at least partly implemented in ATA-133 controllers.
After hitting limits at every factor of 4 (32MB, 128MB, 512MB, 2GB, 8GB, 32GB and most recently 128GB), they've finally got it right.
Take a look here for more details.
Seagate ATA drives aren't the best, but their SCSI drives are. Period. They are the fastest, they are the most reliable, they are the most trusted.
Computer Science is no more about computers than astronomy is about telescopes. --E. W. Dijkstra