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Magnetic Wobbles Cause Hard Drive Failure
An anonymous reader writes "According to this report by IT PRO, scientists working at the University of California have discovered the main reason of hard drive failure. According to researchers, some materials used in hard drives are better at damping spin precession than others. Spin precession of magnetic material effects its neighbors' polarity and this can spread and cause sections of hard drives to spontaneously change polarity and lose data. This is known as a magnetic avalanche. So next time Windows fails to start, you'll know why!"
Spin precession of magnetic material effects its neighbors' polarity
That would be "affects" its neighbours' polarity with an option on calling neighbours' erroneous too - depending on the precise physical phenomena that they are trying to describe.
When 'effect' is used as a verb, it means 'to create.' The article writeup has the same primary-school error. It's not that hard, people.
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True, I would say a machine packed with RAM will wear the drives about 10 times slower than a machine tight on memory. By "tight on memory" I do NOT mean a machine swapping like crazy. A lot of machines tight on memory aren't using their swap-space at all.
The basic principle is that all spare RAM is used as IO buffers and caches thus lowering the number of physical accesses to the drives needed, lowering drive wear and speeding up the machine. You can never have enough RAM, unless you have more RAM than drive space ;-)
Everything I write is lies, read between the lines.
You can run WinPE from a CD too.
It seems possible that this magnetic affectation could be a cause of spontaneous damage the hard drive servo information.
This would cause one of the clicking-type malfunctions which you described, as that "clicking" you hear is the noise the head assembly makes when the drive is rapidly moving it back and forth across the platter attempting to get a fix.
This phenomenon is only one of the several ways for bit rot to creep in and make you lose data.
In bit rot, bits on HDD spontaneously change. It is generally not observable and the results are often blamed on applications and/or OS.
It is lesser known because in the current state of technology, the aplications, OS, filesystem and even RAID can't even detect the problem much less solve them. (RAID doesn't work because it can't tell which copy is right and which is wrong. It assumed what it got from disk is what it wrote to it.)
ZFS (Solaris/SUN filesystem) solves this problem by using end-to-end checksums. However, it exists for few platforms only.
- mritunjai
Here is a link to the UC Santa Cruz press release and the professor is indeed there (I'm sure you can find him). A little spiel from me: I took a class on nanomagnetism this past term and definitely learned about this effect for individual spins and for domains and it has been known for quite some time. Without reading the PRL article because I'm off campus and don't have a personal subscription ($$$ and, hey, this is /.), my guess is that the model explains the why a lot better than existing ones, and how we get from individual precessing spins to the average spin of the entire domain without brute-force computing it, which is nearly impossible.
That being said, different ferromagnetic materials are very different in their interactions between spins and orbits between nearby spins and orbits and so I'm not sure without looking into it how many different ferromagnetic materials this applies too.
I don't see anywhere in TFA that specifies this is the cause of complete hard drive failure. It is, however, a very credible mechanism for the slow increase in bad sectors that is typical of many hard drives. (You young un's may not have heard of this, or seen it, as the hardware/software conspires to hide it from you now-a-days.) I have seen this eventually lead to failure (I.E. unuseability) of a drive.
Since (I would assume) a given manufacturer would tend to use the same materials across a broad span of drive models, this could also be a reasonable explanation for why some manufacturers have reps for 'bad drives'.
Agreed. I'd bet that the mechanical components, specifically the ball-bearings in the drive motor, are more likely to overheat and fail. In addition power-regulation/power-supply components such as large power transistors and resistors on the logic board are likely to fail.
After 5 years of solid running, a lot of hard drives begin to sound different. Guess what, thats the bearings wearing out... More intersting stuff http://storagemojo.com/?p=378
It wasn't more or less on topic, it was a direct response to the closing remark in the summary. Of course hard drive failure may prevent Windows from booting - but it'll prevent any other OS from booting too, so why the unnecessary swipe at Windows?
It's official. Most of you are morons.
IIRC it was a specific few models of maxtor that liked to die, particularly 80-160GB drives.
I have an older 20GB and several newer 250GB and 300GB maxtors and none have died (except one that the delivery man dropped and was replaced free). Before I got these I had a couple of 80GB and a couple of 160GB drives, and those have ALL died now.
Is this the same as what you've seen?
No, it isn't, nor has it ever been.
Hard drives that are used 24/7 fail because their mechanical (moving) parts are built from the cheapest materials that would last for the warranty period. Most of my Western Digital drives develop a noticeable "whine" within a year or two and typically fail soon after that. The "whine" sounds somewhat like an F1 engine running at max rpm, just not as loud (you can hear it if you get your ear close to the drive), and it definitely sounds like there's metal-on-metal friction in the bearings (not good). Better bearings are slightly harder to manufacture and thus no longer used in consumer products. Afterall we're supposed to get products that break and need to be replaced often to keep the manufacturers in bussiness.
You can count on /. for polarizing articles like these.
Most drive manufacturers have gone to fluid bearings. These bearings don't have mechanical contact, the hydroplaning action of the fluid means the bearing parts never touch.
I haven't had a fluid bearing drive fail yet due to bearing failure.
-ted