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Everspin Launches Non-Volatile MRAM That's 500 Times Faster Than NAND
MrSeb writes "Alternative memory standards have been kicking around for decades as researchers have struggled to find the hypothetical holy grail — a non-volatile, low-latency, low-cost product that could scale from hard drives to conventional RAM. NAND flash has become the high-speed, non-volatile darling of the storage industry, but if you follow the evolution of the standard, you'll know that NAND is far from perfect. The total number of read/write cycles and data duration if the drive isn't kept powered are both significant problems as process shrinks continue scaling downward. Thus far, this holy grail remains elusive, but a practical MRAM (Magnetoresistive Random Access Memory) solution took a step towards fruition this week. Everspin has announced that it's shipping the first 64Mb ST-MRAM in a DDR3-compatible module. These modules transfer data at DDR3-1600 clock rates, but access latencies are much lower than flash RAM, promising an overall 500x performance increase over conventional NAND."
This sounds suspiciously like core memory.
Soon the term "core dump" may no longer be an anachronism.
The wheel turns...
A Pirate and a Puritan look the same on a balance sheet.
Q1: Do the DIMMs in your PC run linux?
Q2: Are you DIMM?
non-volatile, low-latency, low-cost
AGoodThing, AnotherGoodThing, YetAnotherGoodThing, pick any two.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Oh noes 800mw. Where ever will be get such levels of power?
The cost is a much bigger issue.
Still completely impractical. It may improve with time, but I wouldn't hold my breath. They basically have to improve fast enough to catch up and then surpass Flash memory, which is difficult at best with the enormous lead Flash memory currently has.
I read the internet for the articles.
It uses a lot more power while you are using it. Because it runs 500x faster you have to use it for a lot less time though, and it doesn't need power to retain state.
It uses 5x more power for that 500x performance. Of course, people will think up new ways to use that kind of performance.
Its 100x more power efficient than NAND.
Not to mention that its fast enough you could use it for primary memory on some systems. Eliminate a whole component out of the system - that saves cost and power. I'm guessing we'll see this in embedded stuff first.
"still years away from practical consumer applications"
I read this as "still years away from BS Rambus patents from the mid 90's to expire"
"I bless every day that I continue to live, for every day is pure profit."
You do know that spinning platters also have a limited lifetime right? Not as low as NAND but it does have a finite lifetime.
For those curious, it performs 500x faster than NAND, costs roughly 50x more than NAND, and uses 5x more power than NAND. All-in-all, not too bad, considering it's new technology and is actually shipping, but it definitely has limited applications at the moment. Assuming they can get the cost down a bit or come up with a few more ideas to reduce power consumption (it's actually worse in older MRAM), it could be something interesting in the near future. I'm guessing MRAM will be showing up more and more often in the next few years, since it seems like it's finally cracked the wall between "cool in the lab" and "semi-practical" after years of being stuck.
The whole point of MRAM is to avoid the limited duration of Flash type memories. Data is stored as a magnetic field. Flash stores data as an electric charge - but the method flash uses to put that charge the is destructive to the insulating layer that keeps it there.
It's actually very durable. "In contrast, MRAM requires only slightly more power to write than read, and no change in the voltage, eliminating the need for a charge pump. This leads to much faster operation, lower power consumption, and an indefinitely long "lifetime"." (https://en.wikipedia.org/wiki/Magnetoresistive_random-access_memory)
Speed = 500x
Price = 50x
Density = 1/64x
Power = 5x
So what you gain in speed, you lose in density, power, and price. Still, if it makes it 500x faster to boot a device, then you could imagine this being great for the embedded market as a boot-up device where the OS resides. The only problem is the 5x power consumption requirement. Maybe the power consumption should be compared to SDRAM, and this might be a good replacement -- imagine not having to wait for the OS in a mobile device to have to write to flash when powering completely down to resume instantly. That might be where this technology finds a niche.
5x more power than NAND
This seems confusing to me, because arguably it's going to use significantly less power than NAND. If I have something to write and it takes NAND 10s at 10w to write it, that's 100J of energy. MRAM would take .02s at 50w, that's 1J of energy. Unless I'm missing something? Seems like they could have quoted that to be both more accurate and show their product in a better light.
You broke the xkcd!
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The requested URL
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That's how the Palm models originally worked, though with battery-backed ram instead of flash.
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What does non volatile mean if it is not durable?
I can't believe I'm having to answer this question on Slashdot, but "non-volatile" in this context means that you can cut power to it and it'll retain the information. The RAM in your computer is an example of volatile storage, since it requires a constant charge in order to preserve the data. NAND, MRAM, tapes, DVDs, HDDs, and a load of other technologies are non-volatile, since they can safely go without power while retaining the data contained within them.
What you're talking about is something else entirely, and you actually have it backwards, since one of the big advantages of MRAM is that it can handle more read/write cycles than NAND. Plus, it's also more stable over time, since NAND that goes without power for too long will eventually lose the electrical charge that preserves the data, whereas MRAM can go for a much longer period of time before its magnetic approach to handling things will fail.
The post was talking about NAND, not MRAM, when it mentioned limited read/write cycles. Current Flash memory technology (i.e. NAND) has an average of about 10,000 read/write cycles before it starts to fail. MRAM does significantly better in this regard.
They claim shipping, so... yeah, a product. However, not a retail product, from the sound of it. Nobody makes a populate-your-own SSD or such.
More importantly perhaps, MRAM supposedly doesn't suffer from the page problem that NAND requires. Individual bits are accessible for reading and writing conveniently, unlike NAND, which requires writing by page. In addition, MRAM is supposedly much more robust than NAND, surviving many more write cycles. It hasn't existed long enough to know this for sure, but in theory, these two advantages means an SSD controller for an MRAM SSD could be vastly simpler than the ones required for NAND. No need for wear-leveling or page rewrite logic. This should both reduce the expense of SSDs and increase their real world performance and reliability.
However, while the article summary blathers about "from hard drives to main memory", this is not a competitor to modern DDR SDRAM. Assuming the quoted 500X faster than NAND is accurate, MRAM latency should be on the order of 100 nanoseconds for a random read. (NAND read latency is on the order of 50 microseconds.) DDR SDRAM random read latency is on the order of 22 nanoseconds.
Having said that, it is comparable with SDRAM from a decade ago, which probably translates directly to modern mobile devices. Low power suspend mode using MRAM instead of SDRAM could conceivably lower mobile device power consumption and improve battery life. If manufacturers get really silly, in theory a mobile device could be built that doesn't distinguish between its main memory and its mass storage. The two functions would be served by the same solid state circuitry. Obviously accommodating such a hardware design would give the kernel guys fits, but it could simplify things in the software a great deal, and incidentally net an interesting performance gain that's visible to users. Notably, the process of launching a program consists of nothing more than creating a stack and a heap for it somewhere--the program's code can stay right where it is. This also results in the somewhat bizarre (to modern ears) situation where suspend mode consists solely of persisting the CPU's state. Memory state is already persistent, always. As a final side effect, once scaled to SSD capacities, a device operating as described above effectively has an absolutely absurd amount of main memory, in theory, equivalent to the entire remaining capacity of the mass storage device.
MRAM has been around in labs for 20 years now, so the possibility of this being a real, viable, product-ready device is reasonably high. MRAM doesn't suffer from Fusion Power Syndrome.
It has much higher performance flash and persistence but at a big cost in size, power and money. I think this sounds like good case for using it as write cache for SSDs that you don't need to flush. Imagine for example a log file that's very volatile, a line gets written every few seconds. Or that document or spreadsheet or email you're working on that Office auto-saves all the time or game autosaves for that matter. With this you could commit it to MRAM and it'd be written "for real" even in case of power failure with no supercap to flush to NAND without wasting write cycles on it. They say a 50:1 cost compared to NAND so on a 256 GB SSD a 512 MB cache should add ~10% to the cost.
If you only need to push the most stale writes to NAND you could download a 50MB installer, install it using 100MB writes then delete the installer and it'd never need to touch the NAND at all - it's marked free again before it's ever written to disk once. Oh yes and you'd also get better burst IOPS as a bonus. If it really can't be worn out like RAM that is going to be huge, even if it just comes on top of the technology we already have and doesn't replace anything. After all, most of my SSD is the same from day to day - the "active set" that gets written to is much smaller.
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We're not too far away from the ultimate limit of smallness on all semiconductor technologies: single atom scale. Flash will stop improving then. More importantly, flash has two important defects: slow write time and an inherent wearout mechanism. So the ultimate (i.e.30 year) question is "can magnetic RAM cells be economically made about the same size as flash?" If the answer is yes, flash becomes obsolete.
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Everspin has announced that it's shipping the first 64Mb ST-MRAM in a DDR3-compatible module. These modules transfer data at DDR3-1600 clock rates, but access latencies are much lower than flash RAM, promising an overall 500x performance increase over conventional NAND.
Wait, so, is this to replace RAM (the mention of DDR3) or to replace drive storage?
These modules transfer data at DDR3-1600 clock rates, but access latencies are much lower than flash RAM
Isn't that comparing apples (DDR3) and oranges (flash RAM)?
systemd is Roko's Basilisk.
There's no mention of any price range
Obviously accommodating such a hardware design would give the kernel guys fits
Already been there and done that. There's an entire "Memory Technology" section in menuconfig to cover all of this, plus the exec-in-place (XIP) stuff for executing programs from memory-addressable storage.
Everspin previously used the crossed-lines writing technique (shown here http://thefutureofthings.com/upload/image/articles/2006/mram/mram-write.jpg), but has now switched to spin-transfer torque based devices. Several other companies are also working on this, so things to improve rapidly. PR release at (http://www.engadget.com/2012/11/14/everspin-throws-first-st-mram-chips-down/)
Yes, but many existing silicon technologies are running up to lots of hurdles right now at current feature sizes, so the single atom problem isn't close to being a concern. Some of the newer technologies not only allow much smaller feature sizes than the current 20nm, but will also allow stacking of components, rather than having a single layer of components as we do now in chips. Not only that, but some are non-volatile, yet fast enough to replace DRAM, so they would have a greater market being able to provide both ram and storage solutions. Hopefully that greater market combined with increased densities will lend itself to greater production and economy of scale. Who really knows though, there may be limits to how much they can produce, and thus the greater market will instead cause them to be priced at a premium. I'm just gonna wait and see, and be hopeful.
From Outer Space?
Whatever happened to the promise of phase-change memory that's supposed to be a million times more rewritable than flash? I have a fuzzy memory of reading a story here about Samsung or HP producing a 512 MB or Mb part that was ready to roll off the lines.
The better question is: if somebody invents a gaseous-state persistent storage technology, would that technology actually be called "VaporWare?"
Unless you're recording video most of the day non stop, or have a DB processing a huge number of transactions(which should be on a server, not your desktop), then a quality SSD should outlast your harddrive. If SSD's had been the forerunners, followed by HDD's, people would be talking about all the things that go wrong with an HDD at 3-5 years lifetime. Except they would probably be just oblivious of the all the failure scenarios that an HDD can suffer. At least with an SSD there is a predictable wearing, and no difficult to predict mechanical wearing. They produce a 10th of the heat as well, but there is conflicting views on whether heat plays a role in HDD failure.
SSDs do seem to have a tendancy to be DOA or die in the first couple of weeks more often than HDDs, but that seems to be a quality control problem unrelated to write endurance. How often that is really the case is hard to say as well without hard statistics, so I emphasize "seem to".
Power != energy. As your own calculation demonstrates. Bravo, you both understand and fail to understand something at the same time! I haven't seen that one before.
Power is energy over time.
I.e. 1 W is 1 joule per second.
The reason this technology requires more power, is that the state changes and reads require more power to be activated than for NAND.
They use less energy, because in order to read or write the same amount of data, they need significantly less time than for NAND.
Since the scale for speed is so much bigger than it is for power, the end result is a reduced energy need - but you still need more power than for NAND.
I'm having flashbacks to linear flash and the Newton. I remember being blown away when I discovered execute-in-place architectures, and frankly I'd like to see them come back.
What part of hitting the process-reduction-scale wall haven't you understood? Right now there's not much boundless confidence that the scale of NAND can be reduced much more without rendering it useless. The already onerous guaranteed obsolescence of the medium is getting worse, not better, with every die shrink. Without some miraculous discovery NAND is rumored to be close to bottoming out, so it seems to me that an upstart technology can make some big leaps in the time it will take NAND designs to make even incremental improvements.
This is /. sir. Using math to solve problems is strictly prohibited. +5 banned for life.
Having to work for a living is the root of all evil.
Bravo, you both understand and fail to understand something at the same time!
Oh my gosh, he's in a quantum-super-imposed state of consciousness!
I haven't seen that one before.
Damn it, now you've observed him and collapsed his waveform. I bet you enjoy killing boxed cats in your spare time, too.
It's solid state flash so it doesn't need refresh nor does it have destructive reads. It's just faster than current SSD's but slower than current gen RAM (1ms vs 100ns vs ~10ns)
100ns RAM was common circa the 486
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And this number of read/write cycles for NAND flash is continuing to fall. Most consumer NAND flash SSDs are now rated for more like 3,000 cycles.
Some of the newer technologies not only allow much smaller feature sizes than the current 20nm, but will also allow stacking of components
Sure we can stack them, but can we cool them? Even the Ivy Bridge chips that lowered power consumption a lot compared to Sandy Bridge increased the watt per mm^2 die size due to the die shrink and now it's up to 77/160 = 0,48 W/mm^2. That is a lot of power you have to dissapate to keep a sane operating temperature. Having a flat chip - ignoring the 3D transistors, which are practically flat for this purpose - connected to a huge heat sink is a pretty effective way of doing that. If you stack the chips many of them won't be on the outside. First they have to transfer all the heat through the other layers, then to the heat sink. Supercomputers have worked on it for decades and they haven't really found a working solution.
Live today, because you never know what tomorrow brings
NOR Flash is more resilient than ST-MRAM in two ways; it requires more than just a write enable line to write or overwrite data and NOR Flash is insensitive to magnetic fields.
Some of the newer technologies not only allow much smaller feature sizes than the current 20nm, but will also allow stacking of components
Sure we can stack them, but can we cool them?
Is there anything carbon nanotubes can't do? Besides, of course, have an acronym that you don't mistake for a naughty word.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
They claim shipping, so... yeah, a product. However, not a retail product, from the sound of it. Nobody makes a populate-your-own SSD or such.
But they do. You can buy a populate-your-own SSD that takes DIMMs. They have a battery backup so that they can refresh themselves. You can use them for cache volumes in contexts where you need a "real" disk. I don't know if you can get anything that takes DDR3 though, and you'd probably need to diddle the firmware to get the right timings for their memories.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
i don't think you get what he means:
it uses more power when reading/writing
but if your computer writes/reads the same data over a period of time, it'll use less power over that period of time (because as you said, it'll use less energy to perform those actions, over this time period, that's power)
It's maximum power draw is indeed 5X higher, but its average power draw under real workloads will be a lot lower?
However, while the article summary blathers about "from hard drives to main memory", this is not a competitor to modern DDR SDRAM. Assuming the quoted 500X faster than NAND is accurate, MRAM latency should be on the order of 100 nanoseconds for a random read. (NAND read latency is on the order of 50 microseconds.) DDR SDRAM random read latency is on the order of 22 nanoseconds.
Why not just visit website of the people who actually make the thing rather than guessing... it's 35ns that's pretty damn close for a just to market technology (how long has SDRAM been around?
source: http://www.everspin.com/products.php?hjk=16&a1f3=0
What happened to PCM otherwise known as Phase Change Memory or PRAM? From what I have read it can be written to like normal memory, address by address unlike flash that is block by block (very important for write speeds). It also boasts faster read and write times as well as one hundred million plus write cycles per memory location vs. flash is what, five thousand. PCM has a memory retention of 300+ years which makes it attractive for long term archival. It is also in production and shipping but density and capacity are not yet on par with nand-flash.
The only downside I see is that it sensitive to higher temperatures that would be encountered during soldering which would erase an already programmed chip. So they have to be programmed in-place vs burned and soldered like flash (or older (E)EPROM technology). It is also a bit challenging to make higher densities and it may be more costly than flash.
I would love to see a PCM disk that is directly attached via PCIe, no SATA overhead. Just an ASIC that presents itself as an ATA controller that has a bunch of PCM hanging off it. You could do it with an FPGA. Open-source SSD anyone? (just a little off topic idea)
You're thinking about just a single use-case. Which would be to replace non-volatile storage, but this could conceivable replace some or all RAM for mobile devices, since it needs no power if not actively reading or writing and would allow even lower power states.
If manufacturers get really silly, in theory a mobile device could be built that doesn't distinguish between its main memory and its mass storage. The two functions would be served by the same solid state circuitry. Obviously accommodating such a hardware design would give the kernel guys fits, but it could simplify things in the software a great deal, and incidentally net an interesting performance gain that's visible to users.
Why would it gives kernel guy fits ? How would it be different to have a swap partition ? Anybody could say me what would be the problem running with no memory and only swap ?
I'm speaking off the top of my head, but I think the memristors supposedly used significantly less power(and hence generate less heat). But they were indeed much much denser, so as you point out, the heat/area might not have been lower. I had never considered that before.
If the only swap you have is a spinning disk, I suspect Linux will not work reliably. There are timeouts in many many places that would be breached repeatedly if all execution required spinning disk I/O.
But see one of the other replies about how the Linux kernel is already outfitted with Execute In Place and everything needed to accommodate the architecture I described, as long as the storage device is fast enough. It has been pointed out elsewhere in the comments that a unified single storage architecture has already been built, in the Palm series of PDAs. Apparently some were made with battery-backed SDRAM as their sole storage.
This is for your sig only.
I wonder how many of those people are illegal immigrants.
I don't know about you but for people who think illegals should be deported should also not count them for values like those.
Even money just giving the poor people wouldn't need to go to the illegals since they would be sent away.
Why don't you guys have friends or journals?
Cooling. That was the problem they had with the Cray-3 which curiously used vertically stacked modules.
They need to increase the density. 64 Mb is pathetic even by DRAM standards.
No.
100 W for 10 seconds is the same amount of power as 100 W for 10 minutes, but it's not the same amount of energy.
It's a bit like speed (meters/second) vs distance (meters). If you travel at 10 m/s for 10 seconds and 10 m/s for 10 minutes, it's the same speed (10 m/s) but not the same distance.
Those numbers are only people who responded to the census.
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