[jleahy]

It's not quite fair to just extrapolate numbers for 256MB of RAM up to a modern system. If this was true you'd be seeing OS crashes daily (if you run hundreds of servers with no ECC you will see mysterious crashes every day, but for one server it might be once a year).

Ultimately these flips are caused by charged particles hitting the memory module (a so called 'single event upset' or SEU), and the number of charged particles hitting the modules has not increased with density (although the modules are more sensitive to SEU, it's a smaller effect).

[vbezhenar]

To encounter a crash, bit flip has to happen on a very small subset of available memory. It's much more likely to just corrupt file cache.

[jleahy]

Well it depends what you're doing, if your memory is full of hash tables and linked lists then you'll likely get a crash (say a web backend). If you're a fileserver and it's all cache then you won't.