[HN Gopher] Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled
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Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled
Author : rbanffy
Score : 98 points
Date : 2021-02-22 10:37 UTC (2 days ago)
(HTM) web link (www.anandtech.com)
(TXT) w3m dump (www.anandtech.com)
| 1996 wrote:
| Is MAMR energy assist similar to SMR - requiring nearby
| information to be rewritten?
| wtallis wrote:
| It shouldn't require re-writing adjacent tracks or sectors.
| Heating up a portion of the platter makes it easier to change
| the bits, but the magnetic field doing the actual writing is
| still pretty narrow. If MAMR/HAMR has any significant effect on
| nearby data, I'd guess it would be similar to DRAM rowhammer:
| repeated writes (and thermal cycles) to one location may cause
| nearby locations to have increased error rates, but that's not
| the same as SMR directly clobbering adjacent tracks.
| dragontamer wrote:
| This seems to have come out of no where.
|
| Helium is an old trick, but MAMR / HAMR (energy assist
| technology, either microwave or heat) was a big announcement from
| Seagate and WD.
|
| I didn't know Toshiba was also working on the tech.
| hart_russell wrote:
| Can someone explain why this FC-MAMR tech is significant?
| wmf wrote:
| Energy-assisted magnetic recording is the next step in the hard
| disk industry roadmap and it's believed to be necessary to
| increase capacity beyond 20 TB.
| dragontamer wrote:
| MAMR isn't necessarily significant per se. It's the energy
| assist in general (be it heat or microwaves).
|
| By heating up a small dot on the disk, that small section will
| change it's bits easier. As such, we can shove more bits into
| the same area.
|
| Energy-assist hard drives is the next step, leading to more and
| more bits in a smaller area.
| burke wrote:
| I remember hearing somewhere that helium will slowly leak through
| whatever vessel you try to contain it with. I wonder if that (is
| true, and if so whether it) imposes some kind of maximum life on
| these drives. Or maybe this is only hydrogen that is this
| problematic.
| duskwuff wrote:
| > I wonder if that (is true, and if so whether it) imposes some
| kind of maximum life on these drives.
|
| It does. Most helium-filled drives expose a SMART attribute (ID
| 22) for how much helium is remaining.
| wccrawford wrote:
| Wouldn't the real problem be other things leaking back in? If
| the helium just leaves, that's a vacuum. If only helium can
| pass, then it's going to stay helium in there.
| thesz wrote:
| Helium can leak into and between crystals in the metal inside
| the container and container itself. That process changes
| dimensions and mechanical properties of construction.
|
| In this particular case I see it as a planned deprecation,
| sort of.
| moonbug wrote:
| drives like this will typically be rated for a 5yr
| operational life.
| GeorgeTirebiter wrote:
| If there is leakage, I wonder how long it would be before
| the data could not be recoverable? Could one transplant
| the platters and 're-charge' the Helium? Or just somehow
| recharge the old disk? Because unless / until we get some
| cheap lots-of-bit storage, all the 'stuff' we're
| generating will not be, in effect, archivable. Is this
| right?
| moonbug wrote:
| Dunno, but disks are consumable items - don't kid
| yourself otherwise.
| foobarian wrote:
| Yay back to syringes and weird jigs and refilling our
| computing accessories with weird chemicals.
| calchris42 wrote:
| I believe helium is used due to it being more effective than
| air at removing heat. Vacuum is significantly less effective
| (as in, no convection in a vacuum)
| theandrewbailey wrote:
| I heard that it was because helium filled drives have less
| drag on platters (thus, are more efficient) than air filled
| drives.
| tyingq wrote:
| No expert, but it seems to make sense that helium is
| particularly hard to contain based on molecular diameter:
| Hydrogen 2.75 Angstroms Helium 2.18 Argon 3.67
| Oxygen 3.64 Nitrogen 3.64 "Air" 3.74
| mschuster91 wrote:
| Fascinating - I had expected helium to be a larger molecule
| than hydrogen.
| Denvercoder9 wrote:
| The given value for hydrogen is for hydrogen gas (i.e. H2),
| while helium is just a single atom.
| tyingq wrote:
| That's what you would expect, though. Helium gas is
| "He1", hydrogen gas is "H2".
| meepmorp wrote:
| I think that was their point: hydrogen gas is diatomic,
| so it makes intuitive sense for it to be larger than
| helium
| rbanffy wrote:
| I'm getting this from memory of my high-school chemistry
| classes, so be careful.
|
| Back then the explanation was that since the He nucleus has
| twice the positive charge as the Hydrogen one, it'd bring
| the electrons a bit closer. Both atoms have a single S
| orbital, He with two electrons.
|
| Also, atomic Hydrogen won't remain atomic for long - it'll
| quickly connect to another Hydrogen so it's S orbitals
| share electrons.
|
| Again, from memory of my high-school chemistry classes (30+
| years ago).
| tyingq wrote:
| There's a detailed explanation here:
| https://chemistry.stackexchange.com/questions/115363/is-a-
| hy...
|
| Edit: Oops. Still relevant since it's H2 in play here, but
| yes, not hyrdrogen vs helium.
| phildenhoff wrote:
| I think that explanation is only about Hydrogen molecules
| and hydrogen atoms, not Hydrogen vs. Helium.
|
| There's a free textbook available here [1] that explains
| that atomic sizes decrease across the periodic table and
| increase down. In short, it decreases across a horizontal
| period because more electrons are in the same orbital
| shell (really a cloud), increasing the negative nuclear
| charge of the cloud, which is more attractive to the
| positive atomic nucleus, so the whole cloud is squeezed
| together, making the whole atom smaller.
|
| [1]: https://chem.libretexts.org/Bookshelves/General_Chem
| istry/Bo...
| Layke1123 wrote:
| This seems unintuitive as I would expect one electron by
| itself to be more closely attracted to a positive nucleus
| instead of when there are two or more fighting to remain
| in "orbit".
|
| Your definition would make sense to me if you can think
| of electrons adding to an over all single electrical
| charge instead of individual electrons, but in that case,
| I have to ask, what is the original reason a single
| electron is repulsed by the atom. I.E. why does it stay
| so far away until more electrons are added. What is the
| force keeping electrons from falling into the nucleus in
| the first place and have an "orbital" or "cloud" at its
| set distance (like one Angstrom or Bohr)?
| btkramer9 wrote:
| My instinctive guess is that it has to do with the spins
| of two electrons "balancing" each other keeping them
| closer to the nucleus.
| blacksmith_tb wrote:
| Yet it takes it weeks or months to leak out (I suppose it'd
| be more accurate to say 'slip between' the other molecules)
| of an extremely thin mylar balloon. I am sure it's an
| engineering challenge to keep it inside a small metal box,
| but it seems possible, at least. After all, the reserves we
| have have just been stuck in the ground, without managing to
| leak into the atmosphere.
| yummypaint wrote:
| This seems like a terrible use of helium from a sustainability
| perspective. There are some things that helium is truly essential
| for, like low temperature cryogenics and neutron detection. Our
| supply is finite and largely tied to natural gas reserves. When
| helium leaks out it floats into space and is gone forever. Why
| does the atmosphere in the drive absolutely have to be helium?
| Why not any other mix of inert gases at optimal pressure for a
| thin air cushion?
|
| Helium is also literally the leakiest thing you can try to
| contain. It will even diffuse out through the metal itself given
| enough time. Not trying to go full tinfoil hat here, but filling
| equipment with helium in this way seems like an effective way to
| cap drive life by time elapsed rather than amount of actual use.
| rarefied_tomato wrote:
| Counterpoint: new large markets & high tech applications for
| helium will drive up the price. At this point consumers might
| scale back the balloons.
| mlyle wrote:
| Note that right now we're burning the natural gas either way.
| How much of the helium we get out depends upon market use of
| natural gas, and market prices about whether we even bother to
| capture the helium from natural gas supplies that are rich in
| helium.
| sandworm101 wrote:
| The amount used in these drives is minuscule, akin to a single
| party balloon. Given these drives are to be used for many years
| at a time, I'll go after them after I manage to stop all the
| birthday balloons.
| FooBarWidget wrote:
| A party balloon full of helium is a minuscule amount?
| sandworm101 wrote:
| Note this is liquid helium in _one_ operational MRI
| machine:
|
| "Let's say you have an MRI scanner with the OR76 magnet
| with the full capacity of 1800 litres of helium. Your
| system consumes approximately 4% of its helium capacity per
| month, that sums up to 48% per year (4% _12 = 48%). That
| means that 864 litres are consumed per year (1800 litres_
| 48% = 864 litres). "
|
| https://lbnmedical.com/liquid-helium-in-mri-machine/
|
| That is liquid, so for the gas we can multiply 864 by about
| 1000. So this MRI machine is using 86,000 liters of helium
| gas per year. That is what, 40,000 party balloons? Say each
| machine does 1000 scans per year, that is a good-sized
| cluster of party balloons for every scan. So yes, a single
| party balloon pales in comparison to the amount of helium
| being used for MRI scans.
|
| (There are near-zero helium MRI machines, but there are
| also plenty of older machines in use out there.)
| temp0826 wrote:
| Thanks, this thread just made "number of party balloons"
| my new favorite unit of measure
| m4rtink wrote:
| Many modern liquid rocket engine powered space launchers
| also use quite a lot of helium for tank pressurisation in
| flight. Helium being inert with very low melting point is
| ideal for this use case, especially with cryogenic
| propelants.
|
| With the most modern generation of reusable space
| launchers such as SpaceX starship an alternative solution
| is being worked on, possible thanks to both fuel
| (methane) and oxidizer (oxygen) they use being cryogenic.
|
| Instead of pressurizing with helium they heat up a bit of
| the cryogenic liquids using the rocket engine heat, let
| it expand into gas and use it to pressurize the tanks, no
| helium required!
|
| One of the reasons is that for fully reusable space
| launchers the main cost is the propelant and helium in
| the amounts needed would be a big part of that!
| moonbug wrote:
| balloon gas is typically about 90% helium and is
| generally a recycling of helium expended in industrial
| applications.
| gibspaulding wrote:
| > "Let's say you have an MRI scanner with the OR76 magnet
| with the full capacity of 1800 litres of helium. Your
| system consumes approximately 4% of its helium capacity
| per month, that sums up to 48% per year (4%12 = 48%).
| That means that 864 litres are consumed per year (1800
| litres 48% = 864 litres)."
|
| I know this is napkin math so it doesn't really matter,
| but a 4% loss times 12 months would be 1-(.96^12) = 39%.
| Unless of course they're topping up the helium every
| month.
| mlyle wrote:
| Loses a percentage of its _capacity_ , not a percentage
| of the amount of helium it has.
| sandworm101 wrote:
| I'm not sure that the percentage matters in cooling. This
| stuff is cooling working parts (magnets). Boiling is
| therefore related to the amount of heat needing to be
| absorbed rather than the amount of helium in the tank. A
| half-empty machine would probably need to boil off just
| as much helium per time/use/work cycle as a full one.
|
| The other error I now realize is that these HDDs probably
| have much less helium than any party balloon. They appear
| to be below atmospheric pressure and are so small that
| they are probably less than a tenth of a liter each. So
| one MRI scan is probably the equivalent of hundreds of
| these HDDs.
| sbierwagen wrote:
| Superconducting magnets don't produce heat. (They are
| superconducting) All the heat comes from the resistive
| feeder cables and the walls of the cryostat.
| rbanffy wrote:
| Does anyone have a number on how much Helium is produced in
| the Earth's crust by radioactive decay?
| sandworm101 wrote:
| Not enough. It is generally known that we are using helium
| faster than the planet can naturally produce it. We
| currently get helium from natural gas deposits. In the
| future we might end up puling it from the air, but that
| would be very expensive. For many use cases it might be
| easier to switch to hydrogen.
|
| For those interested in SETI, excessive atmospheric helium
| might be a detectable techno-signature, a sign that someone
| is digging into deep crust presumably for hydrocarbons.
| system2 wrote:
| When we use the reserves completely and prices sky
| rocket, probably unnecessary entertainment use of it
| would stop.
| rbanffy wrote:
| I am sure we are using it faster than we are extracting
| it, and it'll be interesting to see what happens when
| selling hydrocarbons no longer offsets the cost of
| extracting it, but I was thinking about how much is
| actually produced.
| passivate wrote:
| What gas would you recommend and how does it compare? This
| would be easy to settle using data.
| tyingq wrote:
| Backblaze did a blog post about helium drives in 2018:
|
| https://www.backblaze.com/blog/helium-filled-hard-drive-fail...
|
| Some interesting stuff in there, like the SMART data element
| for helium status. And this quote, after they had 3 years in
| with helium drives:
|
| _" To date only one HGST drive has reported a value of less
| than 100, with multiple readings between 94 and 99."_
|
| But, then, later, this quote:
|
| _" My prediction is that the helium drives will eventually
| prove to have a lower AFR. Why? Drive Days."_
|
| Would be cool if a Backblaze employee could chime in with what
| they've seen since.
| gruez wrote:
| >Would be cool if a Backblaze employee could chime in with
| what they've seen since.
|
| can't you check their follow-up reports they've posted? I
| believe that they break out AFR numbers by drive model so it
| shouldn't be too hard to separate out the helium drives from
| the normal drives.
| xadhominemx wrote:
| Wow you should definitely reach out to the thousands of career
| hard disk engineers to inform them of your idea using different
| inert gases. They probably haven't considered that one.
| abfan1127 wrote:
| my first thought was what happens when it leaks out?
| r00fus wrote:
| Sounds like planned obsolescence.
| moonbug wrote:
| This class of drive will typically have a design life of
| 5yrs at 100% duty.
| wtallis wrote:
| 100% duty cycle on the spindle motors, perhaps. But
| they're definitely not rated for actively performing IO
| 100% of the time.
| colejohnson66 wrote:
| It's not planned obsolescence to include Helium when the
| medium requires it. If you want 18 TB, you're going to need
| Helium (from what I know), but if you want less, you might
| not get it. Planned obsolescence is about _planning_ (hence
| the name) to make a device worse to encourage upgrading.
| The device going bad after a while simply by its nature
| just makes the obsolescence aspect an added benefit.
|
| Is it planned obsolescence that alkaline batteries go bad
| if left unused for a while? That moving parts in a car can
| wear out? I wouldn't say it is.
| rbanffy wrote:
| If the internal pressure in the device is lower than one atm,
| the leakage is easier to contain because it's not helium
| wanting to go out, but air pushing to come in.
|
| Eventually it will happen and the internal drive atmosphere
| will be compromised to a point it doesn't work anymore. By
| then, it should be safe enough to open the drive in a clean
| Helium-filled room and reseal it.
|
| Or just read the data, store it someplace more durable, and
| put the drive in a museum.
| 1996 wrote:
| So it becomes read only when helium leaks out?
| magicalhippo wrote:
| I though it would just lead to more heat, but reading
| this[1] from Seagate it seems indeed possible that the
| drive will not function if too much air gets in:
|
| _Furthermore, the use of a higher number of thinner
| disks is not possible because the windage induces
| turbulence and makes 7200-RPM tracking impossible at the
| desired TPIs. The only way to reduce windage in air-
| filled HDDs is to significantly lower the spindle speed
| (RPM). However, the largest part of the business-critical
| market is not willing to accept lower RPMs due to the
| performance and throughput loss. This means that helium
| HDD technology is the only viable path forward for
| delivering higher capacities because it will allow for an
| increased number of thinner disks._
|
| That said, they also go into the efforts they do to seal
| the helium, so hopefully the helium stays put...
|
| [1]: https://www.seagate.com/files/www-content/product-
| content/en...
| rbanffy wrote:
| I have no idea. May become unreadable if the head can't
| read because the disk is too far (or if it's too close
| and it crashes on the disk)
| yummypaint wrote:
| Thought i would expand on this with some order of magnitude
| leak rate guesses. For a standard small lab vacuum system with
| viton o-rings something like 10-7 mbar _liters /sec (same as
| atm_cc/sec) would be considered acceptable. Assuming the drive
| is pure helium at half pressure with this leak, the loss would
| be on the scale of 3 cc/year. The rate will decrease as the
| partial pressure decreases, but once this becomes significant
| im guessing the drive is already toast.
|
| I would also note that the helium will leak out before
| atmosphere leaks in. If the drives are well sealed they should
| fail due to lack of pressure causing head crash.
| erk__ wrote:
| Tbh I would like to see some calculations of how much helium
| there is in the drive, a quick bit of napkin math makes it seem
| like you can make around 5*10^10 drives with the gas from a
| single field in the US on a single day, assuming that it is at
| 1 atm pressure, though I don't think that would move much more
| than one order of magnitude at most. Though your other point
| still stands.
| ridgeguy wrote:
| I think helium is used for its low kinematic viscosity. That
| lets the R/W head fly closer than, for example, air. The other
| inert gases (Ar, Ne, etc.) have KV values higher than air and
| would give no advantage. He is better for thermal reasons, too.
| pengaru wrote:
| > Not trying to go full tinfoil hat here, but filling equipment
| with helium in this way seems like an effective way to cap
| drive life by time elapsed rather than amount of actual use.
|
| Recognizing planned obsolescence is not tinfoil hat territory.
| It's a rational and predictable commercial practice equivalent
| to rent-seeking, you're not crazy.
| ksec wrote:
| For those who haven't been following HDD closely.
|
| Energy Assisted Magnetic Recording, EAMR is a term that sums up
| both MAMR, Microwave Assisted Magnetic Recording and HAMR, Heat
| Assisted Magnetic Recording.
|
| And this isn't the first 18TB HDD, there are 20TB HDD already.
| Nor the first MAMR drive. Western Digital Ultrastar DC HC550 [1]
| claims that title.
|
| MAMR will bring us some incremental gains, both WD and Seagate
| believes HAMR is the right path in the long term. Seagate shipped
| [2] their first HAMR HDD only last month and my bet is that it
| will take another year before it trickles down to consumer
| market. As of the last investor conference both Seagate and WD
| are still aiming at 50TB HAMR HDD in 2026.
|
| Seagate is also working on Dual-actuator Mach.2 technology, which
| will finally put the HDD transfer speed close to the maximum SATA
| 3 6Gbps speed. Two of these in RAID on a NAS we can finally
| saturate the 10Gbps Ethernet.
|
| Seagate also expect to use HAMR across most range of its product
| to amortised the enormous R&D and component expense with HAMR.
| After all we have been talking about HAMR for nearly a decade.
| Which suggest while we might be getting bigger drive in the near
| future. Price / GB will likely stay flat for another few years. (
| Of course that is also dependent on how fast NAND could drive its
| cost reduction. )
|
| [1] https://www.westerndigital.com/products/data-center-
| platform...
|
| [2] https://www.tomshardware.com/news/seagate-ships-hamr-hdds-
| in...
| Covzire wrote:
| Is transistor density somehow holding back magnetic storage
| density too or something else?
| [deleted]
| ahartmetz wrote:
| Magnetic storage density is held back by how small you can
| make a bit (magnetic domain) and still be able to write it
| AND not have it succumb to random flips due to thermal
| energy. EAMR works by temporarily making tiny magnetic
| domains of a hard to flip material easier to flip while under
| the influence of additional energy.
| wmf wrote:
| No, AFAIK the limit is caused by various tradeoffs between
| the media material and read/write head design (the Magnetic
| Recording Trilemma).
|
| http://www.fgarciasanchez.es/thesisfelipe/node5.html
| shadykiller wrote:
| What happened to memristor based storage revolution ?
| the8472 wrote:
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4479989/
|
| Speaking of storage revolutions, there also was the promised
| MRAM revolution. That never materialized, but at least they're
| shipping useful niche products.
| mcraiha wrote:
| At data copy rate of 100 MB/s taking a backup from one of these
| drives takes 50 hours.
| tecleandor wrote:
| Where did you get that? The specs table says:
|
| Sequential Data Transfer Rate (host to/from drive) 281 MB/s
| magicalhippo wrote:
| For comparisons sake, my 14TB Toshiba MG07ACA14TE drives get
| effectively ~260MB/s outer rim to ~180 MB/s inner rim.
| tlamponi wrote:
| Besides the fact that your BW is off a factor of 2.81, which
| would bring it to ~18.65h, note that:
|
| * That's why they are often rather on the receiving end of
| backups ;-)
|
| * Are often in RAID10 systems, for redundancy/uptime +
| performance, roughly doubling their bandwidth
|
| * Delta syncs/backups exists and thus normally only something
| like tens to hundreds of GiB need to be actually read, that can
| be done i way less than an hour
|
| Depends naturally on the whole setup and actual workload, but
| if you have a high data rate change between backup times you
| may want to go for a SSD only system using ZFS or Ceph or the
| like (again depending on actual use case) which could do both
| cheap differential syncs.
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