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0 pointslucb1e5y ago0 comments

> 1 - 5 bit errors per hour for 8GB of RAM after my calculations

That is way off from what I'm seeing. When launching Factorio I use 90% of my 8GB RAM and never once have I noticed data corruption, and I could tell you how many hours I've played but that would be embarrassing.

The test I did in school with heated-up RAM (the internet said that's when flips should occur more often) also wrote many many gigabytes without a single failure.

Not sure what hardware or temperatures that source is running but it's not DDR3/DDR4 at heats below hairdryer melting temperature because that's where I had to stop the experiment with zero failures.

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anfilt5y ago

I would have to find the paper again, but CPU caches can mask the error rate. The cached values also can overwrite any corruption with correct values. This has interesting side effect of protecting commonly accessed data structures and function pointers from causing out right crashing. Same applies to commonly used values in a computation.

Unless you get a bit flip in data structure pointer or function pointer, it just adds an error to computation, but does not just out crash.

Also we are talking only a handful of errors out billions of calculations.

-Edit Also swap space may keep very rarely accessed data from corruption on the other end of spectrum.