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A comment on ECC matters. Parent comment

Re:ECC matters by dkersten on Sunday January 03, 2021 @12:56PM (#25623449)
Another comment[1] mentioned 1 bitflip per gigabyte per month. If you have a lot of RAM, that's rather a lot.

> It doesn't matter whether a bitflip (unlikely) or some bug (likely) causes a node to spuriously fail

Except that a bitflip can go undetected. It may crash your software or system, but it also may simply leak errors into your data, which can be far more catastrophic.

[1] https://news.ycombinator.com/item?id=25623206

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Re:ECC matters by thequux on Monday January 04, 2021 @09:59AM (#25632090)
I have a server with 384GB of RAM sitting next to me, and in two months of uptime with the only shielding being a pile of IBM iron on top of it, it has detected a grand total of 0 errors.

This is, of course, an anecdote rather than data, but 0 is different enough from the expected 768 that it makes me doubt that statistic.

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Re:ECC matters by jhasse on Sunday January 03, 2021 @01:08PM (#25623573)
So can a bug.
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Re:ECC matters by dkersten on Sunday January 03, 2021 @01:29PM (#25623756)
Yes. And? That doesn't suddenly make bitflips benign.
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Re:ECC matters by incrudible on Sunday January 03, 2021 @03:44PM (#25625055)
The point is that you can't prevent failure by just buying something. You have to deal with the fact that failure can not be prevented.

In other words, if a single defective DIMM somewhere in your deployment is causing catastraphic failure, your mistake was not buying the wrong RAM modules. Your mistake was relying on a single point of failure for mission critical data.

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Re:ECC matters by hda2 on Monday January 04, 2021 @12:52AM (#25628258)
People might not be preventing failure by using ECC, but they significantly decrease the likelihood of having to deal with hard-to-debug problems caused by bitflips.
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