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Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

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Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#81

Post by Dylan16807 »

magicalhippo wrote: post #70
1996 wrote: post #26

Earlier quoted context omitted.

So it becomes read only when helium leaks out?

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 sp…

I'll interpret that as: The drive could be designed with a failsafe lower-RPM mode but it's not worth the engineering budget to allow more than one speed.

Especially looking at WD's "5400 RPM Class" thing as evidence that it takes effort to change the speed of a drive.

Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#82

Post by jlokier »

moonbug wrote: post #61
GeorgeTirebiter wrote: post #59

Earlier quoted context omitted.

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?

Dunno, but disks are consumable items - don't kid yourself otherwise.

I expect some drives to fail within 5 years, but I have many that still have data from much longer ago.

It would be a disconcertingly new phenomenon to find every drive in some old archival NAS failed simultaneously, or every one In a collection of external drives, because all drives last exactly 5 years with little variation, even when switched off, due to helium loss.

Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#83

Post by pfundstein »

plutonorm wrote: post #77
sandworm101 wrote: post #5

Earlier quoted context omitted.

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.

Just use hydrogen for the party balloons

That'd be an exciting party!

Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#84

Post by infofarmer »

mcraiha wrote: post #32

At data copy rate of 100 MB/s taking a backup from one of these drives takes 50 hours.

In a usual medium-to-large cloud configuration where 3-5 redundant copies of each chunk/file/object are randomly and thinly spread across hundreds or thousands of drives, a loss of a single 18TB drive would result in a few minutes of «redundancy repair». No RAIDs would be harmed in the process.

Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#85

Post by Layke1123 »

btkramer9 wrote: post #71
Layke1123 wrote: post #51

Earlier quoted context omitted.

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 repul…

My instinctive guess is that it has to do with the spins of two electrons "balancing" each other keeping them closer to the nucleus.

My understanding is that spin leads to a slightly different electrical force between up and down spinning electrons due to weak force symmetry breaking or singing to that effect. It's more like they have tiny electrical differences rather than canceling out any charge unless I'm mistaken.

Re: Toshiba Unveils First FC-MAMR HDD: 18 TB, Helium Filled

#86

Post by Gravityloss »

m4rtink wrote: post #36
sandworm101 wrote: post #34

Earlier quoted context omitted.

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…

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 (oxy…

In some cases the helium cost is comparable to that of the propellants!

Both are negligible compared to the total cost of space launch currently, but once reusability and operations become more streamlined, they start mattering more.

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