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Seagate Adopts Helium For a 10TB HDD (computerworld.com)
Lucas123 writes: Seagate has finally adopted helium as an inert gas in its data center drives and has used it to produce a 10TB HDD for cloud-based data centers. Seagate had relied on its shingled magnetic recording technology for high-capacity drives right up until its last 8TB HDD, even after WD has used helium in several iterations of its hermetically sealed, 3.5-in HDDs. The lighter-than-air helium reduces friction on platters and allows more to be used. In Seagate's new HDD, it crammed seven platters 14 heads, a 25% increase in disk density over its 8TB drive.
We need to assume that hydrogen will be the next element used for cooling? Or is it the end of spinning disc era?
Hydrogen is used, believe it or not, for generator cooling at power plants. Here is the quick link: https://en.wikipedia.org/wiki/...
Last time I bought a helium hard drive, it floated away and I never saw it again.
I've heard Helium is a finite resource that we are rapidly depleting? I wonder how the use of it on such a large scale will impact the worldwide supply.
Sealing helium in ANYTHING for a significant amount of time is pretty much impossible. Helium is a monatomic gas. These drives will leak.
"Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
Marginal increase in capacity for a major decrease in performance.
404 not found. I'm guessing that means it leaks.
Yes it's another failure mode that is going to give a harder limit on drive life than the current ones of spindle lubricant breaking down and polished surfaces fusing together. Seal things well and maybe they will last ten years before total failure, maybe only five, but a life of a few years is enough to bring them to market.
Heads will crash. The same thing was happening with notebook hard drives on flights because of low atmospheric pressure.
Of course. The drives have to be sealed as tight as a helium tank.
A side benefit is that you can submerse helium drives in an inert coolant.
Actually, wouldn't doing so greatly reduce the leak rate?
Sure helium is monatomic, but it would be surrounded by presumably some kind of mineral oil, or similar material. That could be used to keep the temperature pretty constant, so no great pressure delta would presumably be formed..
Worked for an measurement instrument company building instruments that had to work in helium atmosphere. We tried for a long time to seal the helium out. Even to the point of filling the entire inside with glass filled epoxy to prevent intrusions of helium. In the end we gave up, and did a redesign to work in helium. solid metal seals will work, but pretty much any other seal will not.
don't cut it off www.mgmbill.org
> These drives will leak.
While technically correct, the rate of static-pressure helium leakage through HGST HelioSeal appears to be measured in decades. They up-rated their enterprise SAS drives from 1.4 million hours MTBF to 2.5 million hours MTBF because hermetically-sealing drives and using helium improves various operating parameters, prolonging life in several ways.
My results in production and the lab bear this out over the past two years: helium drives appear to have substantially lower failure rates than air-filled drives. While nobody has owned a commercial helium drive for a decade yet, the internal helium sensors on the disk farms that I've looked at show no degradation or leakage so far: SMART 22 shows 100.
I'll be watching Seagate's results here with great interest and optimism that their results parallel those of HGST.
Disclaimer: I'm an Oracle employee; my opinions do not necessarily reflect those of Oracle or its affiliates.
Matthew P. Barnson
I learn what I think when I read what I write
Wow why wouldn't the skilled engineers at Seagate and Western Digital think of stuff like that?
They should employ you on the spot!
The amount of data you can fit in a normal drive would be a good measure. Some googling says the largest 3.5" HDD is 10TB; the largest 3.5" SSD is 16TB.
It diffuses through metal because it is small. But not as small, nor as diffusion-prone as Hydrogen (which is diatomic btw).
I come here for the love
I don't like the idea of cramming platters to increase density because it throws a wrench in useful scaling relationship between density and I/O rate. I don't want a disk requiring days to sync up or otherwise doubles time needed to read out a given percentage of the disk. This is what archival media is for.
Would much rather see R&D efforts focused on increasing density and therefore I/O performance of individual platters otherwise for my purposes better off simply buying more and scaling out disks.
If helium increases reliability over long term use then great.. if it lasts only as long as the warrantee period I'm not interested.
Hoping against hope something not resembling vaporware will come out of RRAM efforts like crossbar in the next year or two.
Sealing helium in ANYTHING for a significant amount of time is pretty much impossible. Helium is a monatomic gas. These drives will leak.
Leak where? Yes the atoms diffuse through the metal but then what happens to the drive? They aren't pressurized, they are just filled with helium. In order for them to leak other particles need to diffuse into the drive to replace the missing atoms, it's not going to leak itself into a vacuum, just like helium balloons never completely and totally deflate, they just get to the point where the rubber is no longer exerting pressure on the gas.
If you have had hands-on experience with these things: do you have any idea how they handle pressure differences? Hard disk casings typically have flat sides, which are not ideal for handling pressure. In a pressurized airplane, you can have 0.3 bar pressire drop, which will exert about 30 kg of force on the walls. It's worse if they are shipped as unpressurozed cargo. So, the walls must be thicker than with a conventiomal HD, which conflicts with the goal of increasing the number of platters.
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Wow why wouldn't the skilled engineers at Seagate and Western Digital think of stuff like that?
It's because the employees are clowns. I mean literally. They confused the disks with party balloons and started squiirting helium in so they'd float around the room at parties.
Obviously they need a slashdotter to come along and set them right.
SJW n. One who posts facts.
... the internal helium sensors on the disk farms that I've looked at show no degradation or leakage so far: SMART 22 shows 100. ...
Hooray.
Those sensors were manufactured by Volkswagen....
"In order for them to leak other particles need to diffuse into the drive to replace the missing atoms, it's not going to leak itself into a vacuum,"
Actually, you will draw a vacuum, provided that you wait long enough. In balloons, the process slows down not because the pressure difference decreases, but because the latex rubber layer gets thicker as the balloon shrinks.
Citation please. The only reference I've found including in physics textbooks is that helium can diffuse through metals. I haven't found anything that says you can hermetically seal helium in a metal container and then come after a while to find it has drawn a vacuum.
The people making spinning platter drives are just grasping at straws at this point. It won't be more than a decade before SDDs completely take over. You can already get a 1 TB SSD for about $350. A 1 TB HDD costs about $50. That's a ratio of 7:1. SSD prices have been falling a lot over the past year or two, while HDD prices have remained pretty much constant. There's very little reason for most average people to even be using HDDs at the moment apart from people who want to store giant media collections.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
They already have non-consumer 10TB SSD's available in the 2.5 inch form factor. I don't even want to know what the price tag is on those things, but they're supposed to be out there.
A Pirate and a Puritan look the same on a balance sheet.
Let me start with an appeal to authority: I actually get paid to do calculations on gas diffusion and pumping of hydrogen.
Depending on the materials of the walls of your helium-containing vessels, drawing a vacuum can take rather long. The point is that diffusive transport is driven by differences in partial pressures (or concentration if the gas is dissolved in a solid). The partial pressure of helium in the atmosphere is about 0.5 Pa; if you have a vessel with a porous wall with 100 kPa of helium (atmospheric pressure) on the inside, then helium will diffuse towards the volume with the lower partial pressure until both sides have the same partial pressure (i.e., 0.5 Pa). The same process will happen in the opposite direction for other gases (nitrogen, oxygen), but at a much slower speed. So at t=0, you have 100 kPa He (pure). After 1 year, you have (for example) 50 kPa He and 0.01 Pa nitrogen. After ten million years, you have 0.5 Pa He and close to 100 kPa nitrogen.
Just imagine that you have a box with a small hole and lot of fruit flies on the inside. Place this box next to a stable where there are lots of big flies. The fruit flies will gradually disappear from the box, but not because they are pushing each other or because the fat flies (that don't fit through the hole) are pushing them out.
Here are the basics of diffusion: https://en.wikipedia.org/wiki/... .
For helium, diffusion speed is proportional to the difference in partial pressures on either side of the wall. For hydrogen, it's more complicated because the hydrogen molecules first need to dissociate before they can permeate through metals; it turns out that the speed of diffusion is driven by the difference in square roots of the partial pressure of hydrogen on either side.
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In an inflated balloon, you have 1.05 bar of He on the inside and 0.000005 bar of He on the outside.
When the balloon is almost deflated, you have 1.00 bar of He on the inside and 0.000005 bar on the outside. So that would make the diffusion speed decrease by a whopping 5 percent.
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Because the pressure of He inside is equal to the partial pressure of He inside.
Unless the pores in the balloon have diameters that are much larger than the mean free path length (about 50 nm at atmospheric pressure), the absolute pressure doesn't matter for the leak rate, only the partial pressure. I doubt that balloon rubber has pores that large, but it could be. Even in the likely case that the pores are small (<100 nm), the pore size may shrink as the balloon deflates, which will depress the leak rate more than what can be explained from the change in membrane thickness.
Disclosure: I am a vacuum engineer. If you don't believe it, then I suggest that you read up on the concepts of Knudsen number, Fick's law, and permeation.
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