'Racetrack' Memory Could Replace Hard Drives? 149
Galactic_grub writes "An experimental new type of memory that uses nanosecond pulses of electric current to push magnetic regions along a wire could dramatically boost the capacity, speed and reliability of storage devices. Magnetic domains are moved along a wire by pulses of polarized current, and their location is read by fixed sensors arranged along the wire. Previous experiments have been disappointing, but now researchers have found that super-fast pulses of electricity prevent the domains from being obstructed by imperfections in the crystal."
Sounds like... (Score:2, Interesting)
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No, core memory... (Score:5, Interesting)
Looking back, this is all very similar to shift register memory, one of the earliest forms of solid state memory.
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Re:Sounds like... (Score:4, Informative)
http://en.wikipedia.org/wiki/Bubble_memory [wikipedia.org]
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non-volitile (Score:2)
On the other hand, more idiotic things have been done in the past.
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What a nice game, this "guess what he means". I wonder how many more replies there (their/they're/there're) will be.
Delay line memory (Score:2)
I remember tearing apart a small one as a kid - out of a 100 lb 80 x 25 monochrome CRT. A bunch of wire in a foot square metal box.
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They've = they have
There've = there have
So they've updated coil memory would read:
they have updated coil memory or
there have updated coil memory
You know I hate people who correct spelling and grammar on /., but even worse are those who get the correction wrong.
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I do believe, Sir, it was meant in a frolicky fashion, Slashdot Style... I can understand the misconception, Sir.
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Yep, you got me there, that humor went straight over my head. Perhaps you can explain the frolicky fashion that I'm missing
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On the one hand you have the spelling nazi. On the other hand the true-blooded slashdotter with their own logic in spelling. Lately, it seems there is a reaction to the spelling nazi, in which the slashdotter "corrects" some rather OK english into slashdot style spelling.
This particular GGGGP post got a lot of replies stating "you actually mean...". This provokes those with their own particular sense of humor.
There, a joke explained. Please don't complain it is not even remotely funny. A joke explai
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Too true, the explanation was way more funny. **sigh**
I've seen it in fibre before... (Score:3, Interesting)
In some ways being slower is definitely an advantage, even with 100km at 10Gb/s you don't have much storage when the bits are moving at the speed of light.
Re:I've seen it in fibre before... (Score:5, Informative)
The basic technique is even older than that. Google "Mercury Delay Line" for early examples: they'd make a long thin tube of mercury with transponders at each ender. It was around 5 ft per K, IIRC.
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Mod parent up interesting/informative
Re:I've seen it in fibre before... (Score:5, Interesting)
computer architecture. The normal form of instructions
had an "address of next instruction" field.
After getting the program to "work", i.e get the correct
answer, the "optimization" stage consisted of working out how
long each instruction would take, and then positioning the "logically next"
instruction at the location just about to appear out of the delay line.
There was no advantage to inner loops that were faster than the
delay round the mercury loop. Unless you could unroll and fit two
repetitions into one trip round.
Of course, all of this was done by hand.
Plus one addressing (Score:5, Informative)
The optimization was great fun, my favorite part. You could make programs scream if you paid attention.
Re:Plus one addressing (Score:4, Funny)
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How can you be so cruel to the poor poor programs? Sadist.
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Which is your favorite vapourware "hard disk replacement"?
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10 Gbps / c * 100 km = 437.209131 kilobytes
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10Gbps = 1.25GB/s
c = 300,000Km/s (2sf)
Does 100km in 1/3s
1.25GB/s * 1/3 s = 0.416GB
I think your answer is off by a factor of 1000 (or maybe 1024)
Informative? (Score:2)
Does 100km in 1/3s"
Nope, 100km takes 1/3 of a millisecond or 3x10^-4 seconds
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It's a good thing I didn't have a lab at my disposal. I was just a lowly undergrad.
This sounds.... (Score:3, Informative)
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Plus ca change
Bubble memory... (Score:2)
Geez. Every 30 years, or so, everything old is new again. I'm getting tired of this constant repetition in life.
I mean, I was praying *never* to see bell-bottoms ever again, as long as I lived. Shudder.
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Thankfully, you can't see them.
You're funny! (Score:2)
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Every 30 years, or so, everything old is new again
And vice versa. The first time I heard about commercially-available SSDs (solid-state disks), they were being used to replace the aging HDs on industrial PDP-11 systems. The SSDs were more reliable than the RK05/RP07s they replaced and used less power, but it just seemed so wrong to have these SOTA[0] drives hooked up to these ancient machines. Nothing against PDP-11s, they're great, but why does a machine with a cycle time measured in milliseconds need a disk with a couple hundred MB/sec of bandwidth?
Ah, memories... (Score:3, Funny)
One day, when the first protoype of the DHU-11 (we're talking wire-wrap here) was to be demoed, he rigged up a little plastic pipe that ran from the backplane of the PDP 11/24 holding the prototype to a place just out of sight of the various higher-up mucky-mucks who were receiving the demo.
Right after the machine was fired up, he took a big drag on his cigarette and blew into the p
Bubble wrap memory would own! (Score:2)
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lol, bubble WRAP plastic memory would be the shit! Just break the bubbles for all zeros, for each memory update just replace the sheet of bubble wrap and break all the appropriate bubbles again :D
I don't think that you've thought your clever plan all the way through; is there anyone strong-willed enough to resist popping bubble wrap? Imagine a student getting back to their dorm only to find that their roommate has popped all the bubbles on their final dissertation...
Anything (Score:4, Funny)
Re:Anything (Score:5, Insightful)
Hard disks vs Cars (Score:3, Insightful)
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Either that or you're incredibly unlucky.
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Hey, it works and is for the most part reliable. BTW- why does everyone assume that there won't be a need or desire for mechanical systems in the next century? Mechanical engineering and design is far from passe, and will find applications in new fields like space travel in the future.
-b.
Re:Anything (Score:4, Informative)
I know you meant that as a joke, but...
You should take a HDD apart some time. Though manufactured to incredibly small tolerances, they only really have two moving parts - the platters, and the head assembly (which despite having a lot of sub-parts, moves as a single unit).
And aside from them, you don't even have that much else that goes into a HDD - usually two air filters (one for keeping internal air clean, and one that balances external air pressure changes); the body itself (just a big aluminum block with an airtight lid); A magnet assembly for moving the heads; and the electronics on the visible external board. Sometimes you have one more small mechanical bit that doesn't seem to do anything (perhaps it parks the heads for shipping?); And that about covers it.
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(*) Amstrad is a British company who (amongst other things) sold the first *really* successful PC clones on the UK market.
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Every ST-506 interface drive I've ever owned (MFM, RLL, maybe ESDI? I never had any ESDI) required manual parking of the heads. park.com was a required utility back in the DOS days. You only really need to park heads before moving the computer, though.
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(I'm also old enough to remember parking hard drive heads. I thought self-parking drive heads were kind of a miracle.)
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Re:Anything (Score:4, Informative)
In other words, the guys who've been designing hard drives for the past few decades aren't stupid.
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The last time I checked two is an infinitely larger number than zero.
So I'm not knocking HDDs as the R&D, and precision engineering involved is noting to scoff at, but I think we can all agree that it isn't the ideal medium for storage.
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Re:Anything (Score:4, Informative)
Very low-end flash memory has that kind of write cycles. And it's typically limited to NOR flash, which is used only for code memory and limited data store due it its large cell size (largest NOR flash chips are around 256MB). Even so, Intel's StrataFlash had write lifetimes of at least 100,000 erase-write cycles, and most flash chips are underrated by an order of magnitude.
Modern bulk-dsta storage flash is NAND flash, which due to its smaller cell size (partly due to its design, and partly due to operation), means 16GB (byte, not bits) per chip is starting to become practical. NAND flash is faster erasing and writing than NOR flash, but much slower (order of magnitude) slower at reading. Plus it's I/O based - you can't "boot" from NAND flash like you can from NOR. (Write/Erase/Reads are on the order of microseconds for NAND - typically 100-500uS for write/erase, and 10uS for reads. For NOR, writes are typically 300-1000milliseconds, erases 1000ms, but reads on the order of 100ns or less).
Because of the operational characteristics of NAND flash, it typically has a 100,000 write-erase cycle limit at the minimum, with most offering at least 1,000,000 cycles (and typically lasts an order of magnitude more).
Wear-levelling algorithms and bad-block handling increase the time between writes and erases to the point where it almost isn't a consideration anymore - when the drive dies eventually, it'll really be timeto change it. And at least when an SSD dies, it dies on erases and writes, and very rarely on read. So if you get write errors, you still have a great probability of recovering all the data (except the data which was just written).
It's write-erase cycles, because erasing turns "0" bits into "1" bits. Writing turns "1" bits into "0" bits. Within certain restrictions, you can do multiple writes to a block (turning "1" bits into "0" bits, but you can't turn a "0" bit into a "1" bit without erasing), but those don't count towards write-erase cycles. (This behavior is often exploited when marking blocks as dirty and such). And they only fail on writes or erases due to internal timeouts (each cell takes progressively longer and longer to erase and write). Reads can be considered as never failing.
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Goddamn kids (Score:2, Funny)
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Well, actually it's worse than the stone age. Back then we had "Monoliths" which (apart from glacial shift and other geological "features" - or "bugs" as anyone outside sales management called them) had no moving (of movable even) parts at all.
When the storage space on a monolith wasn't enough you could expand to a "Circle".
Still, the space on a full c
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Also, anti-Godwin posts are getting pretty tired, too.
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Victorian age technology (Score:2)
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Who needs nylon? (Score:3, Funny)
says Peter Fischer (Score:1)
Potential for fun (Score:2)
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It's bent in the shape of a "3" (Score:1)
there != their (Score:4, Informative)
I will stop now before I make a simple grammatical error myself.
(yes, I know you're looking, hmm, hmm, must be one here somewhere)
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I'm going to completely ignore the lack of a capital letter and period on that last sentence.
I'm terribly annoyed by the constant inability of people to use the correct word, too, but in the end, none of us are perfect. I
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look more for fault in others than themselves, and not
additionally taking the time to realize that grammar
in english doesn't always work in other languages.
So in fact it is somewhat language specific, and thus
is just in fact something made up by mankind.
Some people think adding layers of complexity to it all
makes them smart, but in fact it is just clutter,
and thus the milestone of the chinese making simplified chinese
I consider a first step in the rig
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Unless you're really replacing yourself with a simple grammatical error, I think you meant, "I will stop now before I make a simple grammatical error, myself."
Everything old is new again (Score:2)
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Downside of everything old being new: Wham! will come back.
I'm pretty sure I prefer to live in the future, not the past...
Hello core memory? (Score:1)
The more things change, (Score:3, Informative)
The more they stay the same.
For those who don't know, delay line memories [wikipedia.org] have been around for at least 50 years...
Kind of interesting that they are using an old concept with new technologies.
Carbon nanotubes? (Score:2)
Maybe it's obvious, but wouldn't carbon nanotubes be a prime suspect, here?
That's not bubble memory... (Score:2, Interesting)
This will bring us one step closer to the Dune Universe. I call dibs on the first load of Spice!
Tatoos (Score:2)
Of course, there is the poo factor....
Wow, Acustic Delay Memory on the nano-scale (Score:2, Interesting)
Polarized current? (Score:2)
Analogous to Human Memory? (Score:2)
If there is such a similarity between this new technology and human memory, that might exp
Racetrack? (Score:3, Interesting)
At least it'll make a crash a lot more fun to watch.
Old news (Score:2, Funny)