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Cosmic rays causing 30k network malfunctions in Japan each year

mainichi.jp

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Re: Cosmic rays causing 30k network malfunctions in Japan each year

#11

Post by contravariant »

belter wrote: post #10

They have to do two things :-) 1) Use ECC memory 2) Go underground "One experiment measured the soft error rate at the sea level to be 5,950 failures in time (FIT = failures per billion hours) per DRAM chip. When the same test setup was moved to an underground vault, shielded by over 50 feet (15 m) of rock that effectively eliminated all cosmic rays, zero soft errors were recorded.[6] In this test, all other causes o…

That's a bit more than just 'go underground'. I've seen people dig for cables but I've never seen them dig a hole 15m deep.

Re: Cosmic rays causing 30k network malfunctions in Japan each year

#17

Post by kevin_nisbet »

shiftpgdn wrote: post #8

Kind of a fun ancedote: In "the old days" when you'd run a server room in your office we had a very large HPC cluster + a significant amount of storage and other one off servers on the top floor of a mid rise office building. I eventually moved it all to a former nuclear fallout facility where our systems were three floors down and under a gigantic pool of water. Error rates and random crashes fell off IMMEDIATELY. I…

Yea, when looking into these myself I did float in conversation that we'd need build a giant pool over our data centers. It was more of a joke though and never went anywhere.

Although our error rate was more like 1-2 per week on the equipment I was looking at.

Re: Cosmic rays causing 30k network malfunctions in Japan each year

#18

Post by tyingq »

belter wrote: post #10

They have to do two things :-) 1) Use ECC memory 2) Go underground "One experiment measured the soft error rate at the sea level to be 5,950 failures in time (FIT = failures per billion hours) per DRAM chip. When the same test setup was moved to an underground vault, shielded by over 50 feet (15 m) of rock that effectively eliminated all cosmic rays, zero soft errors were recorded.[6] In this test, all other causes o…

Polyethylene is supposedly good at blocking cosmic rays. It would be funny to me if the fix was just a drop ceiling full of old grocery bags.

Re: Cosmic rays causing 30k network malfunctions in Japan each year

#19

Post by yummypaint »

fennecfoxen wrote: post #3

> Soft errors occur when the data in an electronic device is corrupted after neutrons, produced when cosmic rays hit oxygen and nitrogen in the earth's atmosphere, collide with the semiconductors within the equipment. Uhhhhhhh. Neutrons? Doubt goes here. I was pretty sure charged particles and ionizing radiation are to blame for messing up your electronics.

One of the ways high energy neutrons interact is by scattering protons elastically. Their masses are essentially the same so the neutron can transfer its momentum very efficiently. These scattered protons (perhaps from plastic in the packaging etc) are then the charged particles that flip bits. These protons are generally lower energy than cosmic ray protons, which means they deposit MORE energy per distance traveled, so they can be worse than cosmics directly.

Re: Cosmic rays causing 30k network malfunctions in Japan each year

#20

Post by andy_ppp »

notum wrote: post #16

Cosmic rays are, or rather were, the reason why manufactures avoid shipping high end cameras by plane, cosmic rays kill pixels in imaging sensors: https://youtu.be/98FZ8C6HneE?t=479 It's also the reason why all ISS footage has dead pixels on it.

Very interesting, so should people who travel with photography equipment take night flights if possible?
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